Carpet, carpet backings and methods

ABSTRACT

The present invention pertains to carpet and method of making it. In one aspect, the carpet includes (a) a primary backing which has a face and a back surface, (b) a plurality of fibers attached to the primary backing and extending from the face of the primary backing and exposed at the back surface of the primary backing, (c) an adhesive backing, (d) an optional secondary backing adjacent to the adhesive backing, and (e) at least one homogeneously branched linear ethylene polymer. The method includes extrusion coating at least one homogeneously branched linear ethylene polymer onto the back surface of a primary backing to provide an adhesive backing. The method can include additional steps or procedures, either separately or in various combinations. Additional steps and procedures include preheating the primary backing prior the extrusion step, multilayer adhesive backings, washing or scouring the primary backing prior the extrusion step, and utilizing adhesive polymeric additives, high heat content fillers, blowing agents and/or implosion agents. The constructions and methods described herein are particularly suited for making carpet tile.

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application is a continuation-in-part application from U.S.Provisional Application No. 60/039,217 filed Feb. 28, 1997, whichapplication was in turn related to pending applications: Ser.No._____________, entitled “ETHYLENE POLYMER CARPET, CARPET BACKINGS ANDMETHODS”; Ser. No._______________ entitled “CARPET BACKINGS AND METHODSUSING SUBSTANTIALLY LINEAR ETHYLENE POLYMERS METHODS”; Ser. No.______________ entitled “CARPETS, CARPET BACKINGS AND METHODS USINGSUBSTANTIALLY LINEAR ETHYLENE POLYMERS METHODS”; and Ser.No._____________ entitled “CARPETS, CARPET BACKINGS AND METHODS USINGHOMOGENEOUS LINEAR ETHYLENE POLYMERS,” all four of which were filed onFeb. 28, 1997, and the disclosures of which are incorporated herein byreference.

FIELD OF THE INVENTION

[0002] This invention relates to carpets and methods of making carpets,wherein, for each, the carpets comprise at least one flexible ethylenepolymer backing material. In a particular instance, the inventionrelates to a carpet and a method of making a carpet by an extrusioncoating technique, wherein for each the carpet comprises a backingmaterial comprised of at least one homogeneously branched linearethylene polymer.

BACKGROUND OF THE INVENTION

[0003] The present invention pertains to any carpet constructed with aprimary backing material and includes tufted carpet and non-tuftedcarpet such as needle punched carpet. Although specific embodiments areamenable to tufted and non-tufted carpet, tufted carpet is preferred.

[0004] As illustrated in FIG. 1, tufted carpets are composite structureswhich include yarn (which is also known as a fiber bundle), a primarybacking material having a face surface and a back surface, an adhesivebacking material and, optionally, a secondary backing material. To formthe face surface of tufted carpet, yarn is tufted through the primarybacking material such that the longer length of each stitch extendsthrough the face surface of the primary backing material. Typically, theprimary backing material is made of a woven or non-woven material suchas a thermoplastic polymer, most commonly polypropylene.

[0005] The face of a tufted carpet can generally be made in three ways.First, for loop pile carpet, the yarn loops formed in the tuftingprocess are left intact. Second, for cut pile carpet, the yarn loops arecut, either during tufting or after, to produce a pile of single yarnends instead of loops. Third, some carpet styles include both loop andcut pile. One variety of this hybrid is referred to as tip-shearedcarpet where loops of differing lengths are tufted followed by shearingthe carpet at a height so as to produce a mix of uncut, partially cut,and completely cut loops. Alternatively, the tufting machine can beconfigured so as to cut only some of the loops, thereby leaving apattern of cut and uncut loops. Whether loop, cut, or a hybrid, the yarnon the back side of the primary backing material comprises tight,unextended loops.

[0006] The combination of tufted yarn and a primary backing materialwithout the application of an adhesive backing material or secondarybacking material is referred to in the carpet industry as raw tuftedcarpet or greige goods. Greige goods become finished tufted carpet withthe application of an adhesive backing material and an optionalsecondary backing material to the back side of the primary backingmaterial. Finished tufted carpet can be prepared as broad-loomed carpetin rolls typically 6 or 12 feet wide. Alternatively, carpet can beprepared as carpet tiles, typically 18 inches square in the UnitedStates and 50 cm. square elsewhere.

[0007] The adhesive backing material is applied to the back face of theprimary backing material to affix the yarn to the primary backingmaterial. Typically, the adhesive backing material is applied by a panapplicator using a roller, a roll over a roller or a bed, or a knife(also called a doctor blade) over a roller or a bed. Properly appliedadhesive backing materials do not substantially pass through the primarybacking material.

[0008] Most frequently, the adhesive backing material is applied as asingle coating or layer. The extent or tenacity to which the yarn isaffixed is referred to as tuft lock or tuft bind strength. Carpets withsufficient tuft bind strength exhibit good wear resistance and, as such,have long service lives. Also, the adhesive backing material shouldsubstantially penetrate the yarn (fiber bundle) exposed on the backsideof the primary backing material and should substantially consolidateindividual fibers within the yarn. Good penetration of the yarn andconsolidation of fibers yields good abrasion resistance. Moreover, inaddition to good tuft bind strength and abrasion resistance, theadhesive material should also impart or allow good flexibility to thecarpet in order to facilitate easy installation of the carpet.

[0009] The secondary backing material is typically a lightweight scrimmade of woven or non-woven material such as a thermoplastic polymer,most commonly polypropylene. The secondary backing material isoptionally applied to the backside of the carpet onto the adhesivebacking material, primarily to provide enhanced dimensional stability tothe carpet structure as well as to provide more surface area for theapplication of direct glue-down adhesives.

[0010] Alternative backing materials may also be applied to the backsideof the adhesive backing material and/or to the backside of the secondarybacking material, if present. Alternative backing materials may includefoam cushioning (e.g. foamed polyurethane) and pressure sensitive flooradhesives. Alternative backing materials may also be applied, forexample, as webbing with enhanced surface area, to facilitate directglue-down adhesive installations (e.g., in contract commercialcarpeting, automobile carpet and airplane carpet where the need forcushioning is ofttimes minimal). Alternative backing materials can alsobe optionally applied to enhance barrier protection respecting moisture,insects, and foodstuffs as well as to provide or enhance firesuppression, thermal insulation, and sound dampening properties of thecarpet.

[0011] Known adhesive backing materials include curable latex, urethaneor vinyl systems, with latex systems being most common. Conventionallatex systems are low viscosity, aqueous compositions that are appliedat high carpet production rates and offer good fiber-to-backingadhesion, tuft bind strength and adequate flexibility. Generally, excesswater is driven off and the latex is cured by passing through a dryingoven. Styrene butadiene rubbers (SBR) are the most common polymers usedfor latex adhesive backing materials. Typically, the latex backingsystem is heavily filled with an inorganic filler such as calciumcarbonate or Aluminum Trihydrate and includes other ingredients such asantioxidants, antimicrobials, flame retardants, smoke suppressants,wetting agents, and froth aids.

[0012] Conventional latex adhesive backing systems can have certaindrawbacks. As one important drawback, typical latex adhesive backingsystems do not provide a moisture barrier. Another possible drawback,particularly with a carpet having polypropylene yarn and polypropyleneprimary and secondary backing materials, is the dissimilar polymer oflatex systems along with the inorganic filler can reduce therecyclability of the carpet.

[0013] In view of these drawbacks, some in the carpet industry havebegun seeking suitable replacements for conventional latex adhesivebacking systems. One alternative is the use of urethane adhesive backingsystems. In addition to providing adequate adhesion to consolidate thecarpet, urethane backings generally exhibit good flexibility and barrierproperties and, when foamed, can eliminate the need for separateunderlayment padding (i.e., can constitute a direct glue-down unitarybacking system). However, urethane backing systems also have importantdrawbacks, including their relatively high cost and demanding curingrequirements which necessitate application at slow carpet productionrates relative to latex systems.

[0014] Thermoplastic polyolefins such as ethylene vinyl acetate (EVA)copolymers and low density polyethylene (LDPE) have also been suggestedas adhesive backing materials due in part to their low cost, goodmoisture stability and no-cure requirements. Various methods areavailable for applying polyolefin backing materials, including powdercoating, hot melt application and extruded film or sheet lamination.However, using polyolefins to replace latex adhesive backings can alsopresent difficulties. For example, U.S. Pat. No. 5,240,530, Table A atCol. 10, indicates that ordinary polyolefin resins possess inadequateadhesion for use in carpet construction. Additionally, relative to latexand other cured systems, ordinary polyolefins have relatively highapplication viscosities and relatively high thermal requirements. Thatis, ordinary thermoplastic polyolefins are characterized by relativelyhigh melt viscosities and high recrystallization or solidificationtemperatures relative to the typical aqueous viscosities and curetemperature requirements characteristic of latex and other cured(thermosetting) systems.

[0015] Even ordinary elastomeric polyolefins, i.e. polyolefins havinglow crystallinities, generally have relatively high viscosities andrelatively high recrystallization temperatures. High recrystallizationtemperatures result in relatively short molten times during processingand, combined with high melt viscosities can make it difficult toachieve adequate penetration of the yam, especially at conventionaladhesive backing application rates.

[0016] One method for overcoming the viscosity and recrystallizationdeficiencies of ordinary polyolefins is to formulate the polyolefinresin as a hot melt adhesive which usually involves formulating lowmolecular weight polyolefins with waxes, tackifiers, various flowmodifiers and/or other elastomeric materials. Ethylene/vinyl acetate(EVA) copolymers, for example, have been used in formulated hot meltadhesive backing compositions and other polyolefins compositions havealso been proposed as hot melt backing compositions. For example, inU.S. Pat. No. 3,982,051, Taft et al. disclose that a compositioncomprising an ethylene/vinyl acetate copolymer, atactic polypropyleneand vulcanized rubber is useful as a hot melt carpet backing adhesive.

[0017] Unfortunately, hot melt adhesive systems are generally considerednot completely suitable replacements for conventional latex adhesivebackings. Typical hot melt systems based on EVA and other copolymers ofethylene and unsaturated comonomers can require considerable formulatingand yet often yield inadequate tuft bind strengths. However, the mostsignificant deficiency of typical hot melt system is their meltstrengths which are generally too low to permit application by a directextrusion coating technique. As such, polyolefin hot melt systems aretypically applied to primary backings by relatively slow, less efficienttechniques such as by the use of heated doctor blades or rotating melttransfer rollers.

[0018] While unformulated high pressure low density polyethylene (LDPE)can be applied by a conventional extrusion coating technique, LDPEresins typically have poor flexibility which can result in excessivecarpet stiffness. Conversely, those ordinary polyolefins that haveimproved flexibility, such as ultra low density polyethylene (ULDPE) andethylene/propylene interpolymers, still do not possess sufficientflexibility, have excessively low melt strengths and/or tend to drawresonate during extrusion coating. To overcome extrusion coatingdifficulties, ordinary polyolefins with sufficient flexibility can beapplied by lamination techniques to insure adequate yarn-to-backingadhesion; however, lamination techniques are typically expensive and canresult in extended production rates relative to direct extrusion coatingtechniques.

[0019] Known examples of flexible polyolefin backing materials aredisclosed in U.S. Pat. Nos. 3,390,035; 3,583,936; 3,745,054; and3,914,489. In general, these disclosures describe hot melt adhesivebacking compositions based on an ethylene copolymer, such as,ethylene/vinyl acetate (EVA), and waxes. Known techniques for enhancingthe penetration of hot melt adhesive backing compositions through theyarn include applying pressure while the greige good is in contact withrotating melt transfer rollers as described, for example, in U.S. Pat.No. 3,551,231.

[0020] Another known technique for enhancing the effectiveness of hotmelt systems involve using pre-coat systems. For example, U.S. Pat. Nos.3,684,600; 3,583,936; and 3,745,054, describe the application of lowviscosity aqueous pre-coats to the back surface of the primary backingmaterial prior the application of a hot melt adhesive composition. Thehot melt adhesive backing systems disclosed in these patents are derivedfrom multi-component formulations based on functional ethylene polymerssuch as, for example, ethylene/ethyl acrylate (EEA) and ethylene/vinylacetate (EVA) copolymers.

[0021] Although there are various systems known in the art of carpetbackings, there remains a need for a thermoplastic polyolefin carpetbacking system which provides adequate tuft bind strength, good abrasionresistance and good flexibility to replace cured latex backing systems.A need also remains for an application method which permits high carpetproduction rates while achieving the desired characteristics of goodtuft bind strength, abrasion resistance, barrier properties andflexibility. Finally, there is also a need to provide a carpet structurehaving fibers and backing materials that are easily recyclable withoutthe necessity of extensive handling and segregation of carpet componentmaterials.

SUMMARY OF THE INVENTION

[0022] In accordance with one aspect of the present invention, a carpetcomprises a plurality of fibers, a primary backing material having aface and a back side, an adhesive backing material and an optionalsecondary backing material, the plurality of fibers attached to theprimary backing material and protruding from the face of the primarybacking material and exposed on the back side of the primary backingmaterial, the adhesive backing material disposed on the back side of theprimary backing material and the optional secondary backing materialadjacent to the adhesive backing material, wherein at least one of theplurality of fibers, the primary backing material, the adhesive backingmaterial or the optional secondary backing material is comprised of atleast one homogeneously branched ethylene polymer characterized ashaving a short chain branching distribution index (SCBDI) of greaterthan or equal to 50 percent.

[0023] Another aspect of the present invention is a method of making acarpet, the carpet including a plurality of fibers, a primary backingmaterial having a face and a back side, an adhesive backing material andan optional secondary backing material, the plurality of fibers attachedto the primary backing material and protruding from the face of theprimary backing material and exposed on the back side of the primarybacking material, the method comprising the step of extrusion coatingthe adhesive backing material or the optional secondary backing materialonto the back side of the primary backing material, wherein theextrusion coated adhesive backing material or optional secondary backingmaterial is comprised of at least one homogeneously branched ethylenepolymer characterized as having a short chain branching distributionindex (SCBDI) of greater than or equal to 50 percent.

[0024] A third aspect of the present invention is a method of making acarpet, the carpet comprising (i) a greige good having a face surfacecomprised of a plurality of fibers attached to a primary backingmaterial having a face and a back side and (ii) an adhesive backingmaterial which comprises at least one homogeneously branched ethylenepolymer characterized as having a short chain branching distributionindex (SCBDI) of greater than or equal to 50 percent and which is inintimate contact with the back side of the primary backing material andhas substantially penetrated and substantially consolidated the fibers,the method comprising extrusion coating the adhesive backing materialonto the back side of the primary backing material and at least oneadditional step selected from the group consisting of

[0025] (a) preheating the greige good prior to the application of theadhesive backing material,

[0026] (b) during the extrusion coating of the adhesive backingmaterial, while at a temperature greater than or equal to the softeningpoint of the adhesive backing material, subjecting the adhesive backingmaterial to a vacuum to draw the adhesive backing material onto the backside of the primary backing material,

[0027] (c) during the extrusion coating of the adhesive backingmaterial, while at a temperature greater than or equal to the softeningpoint of the adhesive backing material, subjecting the adhesive backingmaterial to a positive air pressure device in addition to nip rollpressure to force the adhesive backing material onto the back side ofthe primary backing material, and

[0028] (d) heat soaking the carpet after application of the adhesivebacking material onto the back side of the primary backing material.

[0029] A fourth aspect of the present invention is a carpet comprising aprimary backing material having a face and a back side, yarn attached tothe primary backing material, an adhesive backing material and anoptional secondary backing material, wherein the adhesive backingmaterial comprises at least one homogeneously branched ethylene polymercharacterized as having a short chain branching distribution index(SCBDI) of greater than or equal to 50 percent and is in intimatecontact with the back side of the primary backing material and hassubstantially penetrated the yarn, and wherein the adhesive backingmaterial or optional secondary backing material is comprised of aneffective amount of at least one additive selected from the groupconsisting of a blowing agent and high heat content filler with theproviso that where the blowing agent is selected, the adhesive backingmaterial or the optional secondary backing material is furthercharacterized as having a substantially foamed, frothed or expandednon-collapsed matrix.

[0030] A fifth aspect of the present invention is a method of making acarpet, the carpet comprising yarn attached to a primary backingmaterial and an adhesive backing material, the adhesive backing materialcomprises at least one homogeneously branched ethylene polymercharacterized as having a short chain branching distribution index(SCBDI) of greater than or equal to 50 percent, and wherein the adhesivebacking material is in intimate contact with the primary backingmaterial and has substantially penetrated and substantially consolidatedthe yarn, the method comprising the step of adding an effective amountof a high heat content filler to the adhesive backing material tosubstantially extend the semi-molten or molten time of the adhesivebacking material and enhance the penetration of the adhesive backingmaterial into the yarn.

[0031] A sixth aspect of the invention is a method of making a carpet,the carpet comprising yarn attached to a primary backing material havinga face and a back side and an adhesive backing material comprised of atleast one first and at least one second ethylene polymer layers, whereinthe at least one first ethylene polymer layer is in intimate contactwith the back surface of the primary backing material and the at leastone first ethylene polymer layer has substantially penetrated andsubstantially consolidated the yarn, the at least one first ethylenepolymer layer having a higher melt index than the at least one secondethylene polymer layer and one of the at least first or at least secondethylene polymer layer comprising at least one homogeneously branchedethylene polymer characterized as having a short chain branchingdistribution index (SCBDI) of greater than or equal to 50 percent, themethod comprising the steps of applying the at least one first ethylenepolymer layer directly onto the back surface of the primary backingmaterial and simultaneously or sequentially applying the at least onesecond ethylene polymer layer onto the at least one first ethylenepolymer layer.

[0032] A seventh aspect of the present invention is a method of making acarpet, the carpet having a foamed, frothed or expanded adhesive backingmaterial matrix and comprising yarn attached to a primary backingmaterial, the adhesive backing material comprising at least one ethylenepolymer and is in intimate contact with the primary backing material andhas substantially penetrated and substantially consolidated the yarn,the method comprising the step of adding an effective amount of at leastone blowing agent to the adhesive backing material and thereafteractivating the blowing agent to foam, froth or expand the adhesivebacking material.

[0033] An eighth aspect of the present invention is a method of making acarpet, the carpet having a collapsed, non-expanded adhesive backingmaterial matrix and comprising yarn attached to a primary backingmaterial, the adhesive backing material comprising at least one ethylenepolymer and is in intimate contact with the primary backing material andhas substantially penetrated and substantially consolidated the yarn,the method comprising the step of adding an effective amount of at leastone implosion agent to the adhesive backing material and thereafteractivating the implosion agent during an extrusion coating step suchthat molten or semi-molten polymer is forced into the free space of yarnexposed on the backside of the primary backing material.

[0034] A ninth aspect of the present invention is a method of making acarpet, the carpet having a face surface and comprising yarn, a primarybacking material, an adhesive backing material and an optional secondarybacking material, wherein the primary backing material has a backsurface opposite the face surface of the carpet, the yarn is attached tothe primary backing material, the adhesive backing material is appliedto the back surface of the primary backing material and the optionalsecondary backing material is applied onto the adhesive backingmaterial, the method comprising the step of scouring or washing the backsurface of the primary backing material prior to the application of theadhesive backing material to substantially remove or displace processingmaterials.

[0035] A tenth aspect of the present invention is a carpet comprising aprimary backing material having a face and a back side, yarn attached tothe primary backing material, an adhesive backing material and anoptional secondary backing material, wherein the adhesive backingmaterial comprises at least one homogeneously branched ethylene polymercharacterized as having a short chain branching distribution index(SCBDI) of greater than or equal to 50 percent, at least one adhesivepolymeric additive and is in intimate contact with the back side of theprimary backing material and has substantially penetrated the yarn.

[0036] An eleventh aspect of the present invention is a method of makinga carpet, and the carpet so made, which includes the steps of providinga primary backing material having a face and a back side, tufting a yarninto the primary backing material to produce a carpet pile on the faceside of the primary backing material and loops of the yarn on the backside of the primary backing material, providing an aqueous dispersion ofpolyolefin particles, applying the dispersion to the back side of theprimary backing material, and then applying heat to the dispersion todry the dispersion and to at least partially melt the polyolefinparticles and thereby fix the loops of yarn to the primary backingmaterial.

[0037] A twelfth aspect of the invention is a method of making a carpet,and the carpet so made, which method includes the steps of providing aprimary backing material having a face and a back side, tufting a yarninto the primary backing material to produce a carpet pile on the faceside of the primary backing material and loops of the yarn on the backside of the primary backing material, extruding a first sheet of a firstthermoplastic material to the back side of the primary backing, andextruding a second sheet of a second thermoplastic material adjacent thefirst sheet. In this twelfth aspect, the melt viscosity of thethermoplastic material in the first sheet is lower than the meltviscosity of the thermoplastic material in the second sheet so as toprovide for enhanced penetration of the thermoplastic material in thefirst sheet into at least one of the primary backing material or theloops of yarn on the back side of the primary backing material.

[0038] A thirteenth aspect of the present invention is a method ofmaking a carpet with an extruded sheet as part of its backing whereinprior to the extruding step, at least the back side of the primarybacking and loops of the yarn on the back side of the primary backingare treated to remove undesirable chemicals from the surface and therebyenhance the adhesion of the extruded sheet.

[0039] A fourteenth aspect of the present invention is a carpet tilewith an extruded backing. Preferably, the carpet tile is made with afirst and second extruded sheet and a reinforcing material embeddedbetween the two sheets.

BRIEF DESCRIPTION OF THE DRAWINGS

[0040]FIG. 1 is an illustration of a tufted carpet 10.

[0041]FIG. 2 is a schematic representation of an extrusion coating line20 for making a carpet 70.

[0042]FIG. 3 consists of scanning electron microscopy photomicrographsat 20× magnification (3a) and 50× magnification (3b) illustrating theinterfaces of the various carpet components of Example 14.

[0043]FIG. 4 consists of scanning electron microscopy photomicrographsat 20× magnification (4a) and 50× magnification (4b) illustrating theinterfaces of the various carpet components of Example 22.

[0044]FIG. 5 is a X-Y plot of the effect of fiber bundle penetration bythe adhesive backing material on the abrasion resistance performance ofpolypropylene and nylon carpet samples.

[0045]FIG. 6 is a cross-section showing the construction of a carpettile in accordance with the present invention.

[0046]FIG. 7 is a schematic representation of an extrusion coating linefor making carpet tile according to the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0047] The terms “intimate contact,” “substantial encapsulation,” and/or“substantial consolidation” are used herein to refer to mechanicaladhesion or mechanical interactions (as opposed to chemical bonding)between dissimilar carpet components, irrespective of whether or not oneor more carpet component is capable of chemically interacting withanother carpet component. With respect to the mechanical adhesion orinteractions of the present invention, there may be some effectiveamount of intermixing or inter-melting of polymeric materials; however,there is no continuous or integral fusing of various components asdetermined from visual inspection of photomicrographs (at 20×magnification) of the various carpet interfaces. Within this meaning,fusion of yarn or fiber bundles or of individual fibers to one anotherwithin a fiber bundle is not considered integral fusion in itself sincefibers are referred to herein as one carpet component.

[0048] The term “intimate contact” refers to the mechanical interactionbetween the back surface of the primary backing material and theadhesive backing material. The term “substantial encapsulation” refersto the adhesive backing material significantly surrounding the yarn orfiber bundles at or in immediate proximity to the interface between theback surface of the primary backing material and the adhesive backingmaterial. The term “substantial consolidation” refers to the overallintegrity and dimensional stability of the carpet that is achieved bysubstantially encapsulating the yarn or fiber bundles and intimatelycontacting the back surface of the primary backing material with theadhesive backing material. A substantially consolidated carpet possessesgood component cohesiveness and good delamination resistance withrespect to the various carpet components.

[0049] The term “integral fusing” is used herein in the same sense asknown in the art and refers to heat bonding of carpet components using atemperature above the melting point of the adhesive backing material.Integral fusing occurs when the adhesive backing material comprises thesame polymer as either the fibers or primary backing material or both.However, integral fusing does not occur when the adhesive backingmaterial comprises a different polymer than the fibers and primarybacking material. By the term “same polymer,” it is meant that themonomer units of the polymers are of the same chemistry, although theirmolecular or morphological attributes may differ. Conversely, by theterm “different polymer,” it is meant that, irrespective of anymolecular or morphological differences, the monomer units of thepolymers are of different chemistries. Thus, in accordance with thevarious definitions of the present invention, a polypropylene primarybacking material and a polyethylene adhesive backing material would notintegrally fuse because these carpet components are of differentchemistries.

[0050] The term “carpet component” is used herein to refer separately tocarpet fiber bundles, the primary backing material, the adhesive backingmaterial and the optional secondary backing material.

[0051] The term “extrusion coating” is used herein in its conventionalsense to refer to an extrusion technique wherein a polymer compositionusually in pellet-form is heated in an extruder to a temperatureelevated above its melt temperature and then forced through a slot dieto form a semi-molten or molten polymer web. The semi-molten or moltenpolymer web is continuously drawn down onto a continuously fed greigegood to coat the backside of the greige good with the polymercomposition. FIG. 2 illustrates an extrusion process of the presentinvention wherein, at the nip, the face surface of the greige good isoriented towards the chill roll and the back surface of the adhesivebacking material oriented is towards the nip pressure roll. Extrusioncoating is distinct from a lamination technique.

[0052] The term “lamination technique” is used herein in itsconventional sense refer to applying adhesive backing materials togreige goods by first forming the adhesive backing material as asolidified or substantially solidified film or sheet and thereafter, ina separate processing step, reheating or elevating the temperature ofthe film or sheet before applying it to the back surface of the primarybacking material.

[0053] The term “heat content” is used herein to refer to themathematical product of the heat capacity and specific gravity of afiller. Fillers characterized as having high heat content are used inspecific embodiments of the present invention to extend thesolidification or molten time of adhesive backing materials. TheHandbook for Chemical Technicians, Howard J. Strauss and MiltonKaufmann, McGraw Hill Book Company, 1976, Sections 1-4 and 2-1 providesinformation on the heat capacity and specific gravity of select mineralfillers. The fillers suitable for use in the present invention do notcharge their physical state (i.e., remain a solid material) over theextrusion coating processing temperature ranges of the presentinvention. Preferred high heat content fillers possess a combination ofa high specific gravity and a high heat capacity.

[0054] The term “implosion agent” is used herein to refer to the use ofconventional blowing agents or other compounds which out-gas or causeout-gassing when activated by heat, usually at some particularactivation temperature. In the present invention, implosion agents areused to implode or force adhesive backing material into the free spaceof yarn or fiber bundles.

[0055] The term “processing material” is used herein to refer tosubstances such as spin finishing waxes, equipment oils, sizing agentsand the like, which can interfere with the adhesive or physicalinterfacial interactions of adhesive backing materials. Processingmaterials can be removed or displaced by a scouring or washing techniqueof the present invention whereby improved mechanical bonding isaccomplished.

[0056] The terms “polypropylene carpet” and “polypropylene greige goods”are used herein to mean a carpet or greige goods substantially comprisedof polypropylene fibers, irrespective of whether the primary backingmaterial for the carpet or greige good is comprised of polypropylene orsome other material.

[0057] The terms “nylon carpet” and “nylon greige goods” are used hereinto mean a carpet or greige goods substantially comprised of nylonfibers, irrespective of whether the primary backing material for thecarpet or greige good is comprised of nylon or some other material.

[0058] The term “linear” as used to describe ethylene polymers is usedherein to mean the polymer backbone of the ethylene polymer lacksmeasurable or demonstrable long chain branches, e.g., the polymer issubstituted with an average of less than 0.01 long branch/1000 carbons.

[0059] The term “homogeneous ethylene polymer” as used to describeethylene polymers is used in the conventional sense in accordance withthe original disclosure by Elston in U.S. Pat. No. 3,645,992, to referto an ethylene polymer in which the comonomer is randomly distributedwithin a given polymer molecule and wherein substantially all of thepolymer molecules have substantially the same ethylene to comonomermolar ratio. As defined herein, both substantially linear ethylenepolymers and homogeneously branched linear ethylene are homogeneousethylene polymers.

[0060] Homogeneously branched ethylene polymers are homogeneous ethylenepolymers that possess short chain branches and that are characterized bya relatively high short chain branching distribution index (SCBDI) orrelatively high composition distribution branching index (CDBI). Thatis, the ethylene polymer has a SCBDI or CDBI greater than or equal to 50percent, preferably greater than or equal to 70 percent, more preferablygreater than or equal to 90 percent and essentially lack a measurablehigh density (crystalline) polymer fraction.

[0061] The SCBDI or CDBI is defined as the weight percent of the polymermolecules having a comonomer content within 50 percent of the mediantotal molar comonomer content and represents a comparison of thecomonomer distribution in the polymer to the comonomer distributionexpected for a Bernoullian distribution. The SCBDI or CDBI ofpolyolefins can be conveniently calculated from data obtained fromtechniques known in the art, such as, for example, temperature risingelution fractionation (abbreviated herein as “TREF”) as described, forexample, by Wild et al., Journal of Polymer Science, Poly. Phys. Ed,Vol. 20, p. 441 (1982), L. D. Cady, “The Role of Comonomer Type andDistribution in LLDPE Product Performance,” SPE Regional TechnicalConference, Quaker Square Hilton, Akron, Ohio, October 1-2, pp. 107-119(1985), or in U.S. Pat. Nos. 4,798,081 and 5,008,204. However, thepreferred TREF technique does not include purge quantities in SCBDI orCDBI calculations. More preferably, the comonomer distribution of thepolymer and SCBDI or CDBI are determined using ¹³C NMR. analysis inaccordance with techniques described, for example, in U.S. Pat. No.5,292,845 and by J. C. Randall in Rev. Macromol. Chem. Phys., C29, pp.201-317.

[0062] The terms “homogeneously branched linear ethylene polymer” and“homogeneously branched linear ethylene/^(a)-olefin polymer” means thatthe olefin polymer has a homogeneous or narrow short branchingdistribution (i.e., the polymer has a relatively high SCBDI or CDBI) butdoes not have long chain branching. That is, the linear ethylene polymeris a homogeneous ethylene polymer characterized by an absence of longchain branching. Such polymers can be made using polymerizationprocesses (e.g., as described by Elston in U.S. Pat. No. 3,645,992)which provide a uniform short chain branching distribution (i.e.,homogeneously branched). In his polymerization process, Elston usessoluble vanadium catalyst systems to make such polymers, however others,such as Mitsui Petrochemical Industries and Exxon Chemical Company, havereportedly used so-called single site catalyst systems to make polymershaving a homogeneous structure similar to polymer described by Elston.U.S. Pat. No. 4,937,299 to Ewen et al. and U.S. Pat. No. 5,218,071 toTsutsui et al. disclose the use of metallocene catalysts, such ascatalyst systems based on hafnium, for the preparation of homogeneouslybranched linear ethylene polymers. Homogeneously branched linearethylene polymers are typically characterized as having a molecularweight distribution, M_(w)/M_(n), of less than 3, preferably less than2.8, more preferably less than 2.3. Commercial examples of suitablehomogeneously branched linear ethylene polymers include those sold byMitsui Petrochemical Industries as Tafmer™ resins and by Exxon ChemicalCompany as Exact™ resins and Exceed™ resins.

[0063] The terms “homogeneous linearly branched ethylene polymer” or“homogeneously branched linear ethylene/^(a)-olefin polymer” do notrefer to high pressure branched polyethylene which is known to thoseskilled in the art to have numerous long chain branches. The term“homogeneous linear ethylene polymer” generically refers to both linearethylene homopolymers and to linear ethylene/^(a)-olefin interpolymers.A linear ethylene/^(a)-olefin interpolymer possesses short chainbranching and n the ^(a)-olefin is typically at least one C₃-C₂₀^(a)-olefin (e.g., propylene, 1-butene, 1-pentene, 4-methyl-1-pentene,1-hexene, and 1-octene).

[0064] When used in reference to an ethylene homopolymer (i.e., a highdensity ethylene polymer not containing any comonomer and thus no shortchain branches), the term “homogeneous ethylene polymer” or “homogeneouslinear ethylene polymer” means the polymer was made using a homogeneouscatalyst system such as, for example, that described Elston or Ewen orthose described by Canich in U.S. Pat. Nos. 5,026,798 and 5,055,438, orby Stevens et al. in U.S. Pat. No. 5,064,802.

[0065] The term “substantially linear ethylene polymer” is used hereinto refer specially to homogeneously branched ethylene polymers that havelong chain branching. The term does not refer to heterogeneously orhomogeneously branched ethylene polymers that have a linear polymerbackbone. For substantially linear ethylene polymers, the long chainbranches have the same comonomer distribution as the polymer backbone,and the long chain branches can be as long as about the same length asthe length of the polymer backbone to which they are attached. Thepolymer backbone of substantially linear ethylene polymers issubstituted with about 0.01 long chain branches/1000 carbons to about 3long chain branches/1000 carbons, more preferably from about 0.01 longchain branches/1000 carbons to about 1 long chain branches/1000 carbons,and especially from about 0.05 long chain branches/1000 carbons to about1 long chain branches/1000 carbons.

[0066] Long chain branching is defined herein as a chain length of atleast 6 carbons, above which the length cannot be distinguished using¹³C nuclear magnetic resonance spectroscopy. The presence of long chainbranching can be determined in ethylene homopolymers by using ¹³Cnuclear magnetic resonance (NMR) spectroscopy and is quantified usingthe method described by Randall (Rev. Macromol. Chem. Phys., C29, V.2&3, p. 285-297).

[0067] Although current ¹³C nuclear magnetic resonance spectroscopycannot determine the length of a long chain branch in excess of sixcarbon atoms, there are other known techniques useful for determiningthe presence of long chain branches in ethylene polymers, includingethylene/1-octene interpolymers. Two such methods are gel permeationchromatography coupled with a low angle laser light scattering detector(GPC-LALLS) and gel permeation chromatography coupled with adifferential viscometer detector (GPC-DV). The use of these techniquesfor long chain branch detection and the underlying theories have beenwell documented in the literature. See, e.g., Zimm, G. H. andStockmayer, W. H., J. Chem. Phys., 17, 1301 (1949) and Rudin, A., ModernMethods of Polymer Characterization, John Wiley & Sons, New York (1991)pp. 103-112.

[0068] A. Willem deGroot and P. Steve Chum, both of The Dow ChemicalCompany, at the Oct. 4, 1994 conference of the Federation of AnalyticalChemistry and Spectroscopy Society (FACSS) in St. Louis, Miss.,presented data demonstrating that GPC-DV is a useful technique forquantifying the presence of long chain branches in substantially linearethylene polymers. In particular, deGroot and Chum found that the levelof long chain branches in substantially linear ethylene homopolymersamples measured using the Zimm-Stockmayer equation correlated well withthe level of long chain branches measured using ¹³C NMR.

[0069] Further, deGroot and Chum found that the presence of octene doesnot change the hydrodynamic volume of the polyethylene samples insolution and, as such, one can account for the molecular weight increaseattributable to octene short chain branches by knowing the mole percentoctene in the sample. By deconvoluting the contribution to molecularweight increase attributable to 1-octene short chain branches, deGrootand Chum showed that GPC-DV may be used to quantify the level of longchain branches in substantially linear ethylene/octene copolymers.

[0070] DeGroot and Chum also showed that a plot of Log(I₂, melt index)as a function of Log(GPC Weight Average Molecular Weight) as determinedby GPC-DV illustrates that the long chain branching aspects (but not theextent of long branching) of substantially linear ethylene polymers arecomparable to that of high pressure, highly branched low densitypolyethylene (LDPE) and are clearly distinct from ethylene polymersproduced using Ziegler-type catalysts such as titanium complexes andordinary homogeneous catalysts such as hafnium and vanadium complexes.

[0071] For substantially linear ethyierie polymers, the long chainbranch is longer than the short chain branch that results from theincorporation of the ^(a)-olefin(s) into the polymer backbone. Theempirical effect of the presence of long chain branching in thesubstantially linear ethylene polymers used in the invention ismanifested as enhanced rheological properties which are quantified andexpressed herein in terms of gas extrusion rheometry (GER) resultsand/or melt flow, I₁₀/I₂, increases.

[0072] Substantially linear ethylene polymers are homogeneously branchedethylene polymers and are disclosed in U.S. Pat. Nos. 5,272,236 and5,278,272. Homogeneously branched substantially linear ethylene polymersare available from The Dow Chemical Company as AFFINITY™ polyolefinplastomers and from Dupont Dow Elastomers JV as ENGAGE™ polyolefinelastomers. Homogeneously branched substantially linear ethylenepolymers can be prepared via the solution, slurry, or gas phasepolymerization of ethylene and one or more optional ^(a)-olefincomonomers in the presence of a constrained geometry catalyst, such asthe method disclosed in European Patent Application 416,815-A.Preferably, a solution polymerization process is used to manufacture thesubstantially linear ethylene polymer used in the present invention.

[0073] The terms “heterogeneous” and “heterogeneously branched” meanthat the ethylene polymer is characterized as a mixture of interpolymermolecules having various ethylene to comonomer molar ratios.Heterogeneously branched ethylene polymers are characterized as having ashort chain branching distribution index (SCBDI) less than about 30percent. Heterogeneously branched linear ethylene polymers are availablefrom The Dow Chemical Company as DOWLEX™ linear low density polyethyleneand as ATTANE™ ultra-low density polyethylene resins. Heterogeneouslybranched linear ethylene polymers can be prepared via the solution,slurry or gas phase polymerization of ethylene and one or more optionalalpha-olefin comonomers in the presence of a Ziegler Natta catalyst, byprocesses such as are disclosed in U.S. Pat. No. 4,076,698 to Andersonet al. Heterogeneously branched ethylene polymers are typicallycharacterized as having molecular weight distributions, M_(w)/M_(n), inthe range of from 3.5 to 4.1 and, as such, are distinct fromsubstantially linear ethylene polymers and homogeneously branched linearethylene polymers in regards to both compositional short chain branchingdistribution and molecular weight distribution.

[0074] The substantially linear ethylene polymers used in the presentinvention are not in the same class as homogeneously branched linearethylene polymers, nor heterogeneously branched linear ethylenepolymers, nor are substantially linear ethylene polymers in the sameclass as traditional highly branched low density polyethylene (LDPE).The substantially linear ethylene polymers useful in this inventionsurprisingly have excellent processability, even though they haverelatively narrow molecular weight distributions (MWDs). Even moresurprising, the melt flow ratio (I₁₀/I₂) of the substantially linearethylene polymers can be varied essentially independently of thepolydispersity index (i.e., molecular weight distribution(M_(w)/M_(n))). This is contrasted with conventional heterogeneouslybranched linear polyethylene resins which have rheological propertiessuch that as the polydispersity index increases, the I₁₀/I₂ value alsoincreases. The rheological properties of substantially linear ethylenepolymers also differ from homogeneously branched linear ethylenepolymers which have relatively low, essentially fixed I₁₀/I₂ ratios.

[0075] We have discovered that substantially linear ethylene polymersand homogeneously branched linear ethylene polymers (i.e., homogeneouslybranched ethylene polymers) offer unique advantages for extrusion coatedcarpet backing applications, especially for commercial and residentialcarpet markets. Homogeneously branched ethylene polymers (includingsubstantially linear ethylene polymers in particular) have lowsolidification temperatures, good adhesion to polypropylene, and lowmodulus relative to conventional ethylene polymers such as low densitypolyethylene (LDPE), heterogeneously branched linear low densitypolyethylene (LLDPE), high density polyethylene (HDPE), andheterogeneously branched ultra low density polyethylene (ULDPE). Assuch, homogeneously branched ethylene polymers are useful for makingcarpet fibers, primary backing materials, adhesive backing materials andoptional secondary backing materials. However, homogeneously branchedethylene polymers are particularly useful as adhesive backing materialsfor tufted carpet and non-tufted carpet (e.g., needle-punched carpet)and are especially useful for tufted carpets.

[0076] In the present invention, during extrusion coating of thebackside of carpet to apply an adhesive backing material, properlyselected substantially linear ethylene polymers and homogeneouslybranched linear ethylene polymers show good penetration of carpet yarns(fiber bundles) and also allow good consolidation of the fibers withinthe yarn. When used for tufted carpets, the tuft bind strength andabrasion resistance of the carpet is increased by the penetration ofsubstantially linear ethylene polymers and homogeneously branched linearethylene polymers into the yarn. Preferably, a tuft bind (or tuft lock)strength of 3.25 pounds (1.5 kg) or more is achieved, more preferably 5pounds (2.3 kg) or more and most preferably 7.5 pounds (3.4 kg) or more.In addition to improved penetration of the yarn, tuft bind strength canbe also be increased by increasing the molecular weight of the polymer.However, a higher polymer molecular weight selected for improved tuftbind strength is contra to the requirement of a lower polymer molecularweight which is generally needed for good yarn penetration and goodextrusion coatability. Also, higher polymer densities are desirable forimproved chemical and barrier resistance, yet higher densitiesinvariably yield stiffer carpets. As such, polymer properties must bechosen such that a balance is maintained between extrusion coatabilityand abrasion resistance as well as between chemical resistance andcarpet flexibility.

[0077] When carpet greige goods are backed with properly selectedsubstantially linear ethylene polymers or homogeneously branched linearethylene polymers, the low flexural modulus of these polymers offersadvantages in ease of carpet installation and general carpet handling.Substantially linear ethylene polymers, in particular, when employed asan adhesive backing material show enhanced mechanical adhesion topolypropylene which improves the consolidation and delaminationresistance of the various carpet layers and components, i.e.,polypropylene fibers, fiber bundles, the primary backing material, theadhesive backing material and the secondary backing material whenoptionally applied. Consequently, exceptionally good abrasion resistanceand tuft bind strength can be obtained. Good abrasion resistance isespecially important in commercial carpet cleaning operations as goodabrasion resistance generally improves carpet durability.

[0078] Properly selected substantially linear ethylene polymers canallow the elimination of secondary backing materials and as such canresult in significant manufacturing cost savings. In addition, carpetsadhesively backed with a substantially linear ethylene polymer orhomogeneously branched linear ethylene polymer can provide a substantialfluid and particle barrier which enhances the hygienic properties ofcarpet.

[0079] A substantially linear ethylene polymer or homogeneously branchedlinear ethylene polymer adhesive backing material can allow totallyrecyclable carpet products particularly where the carpet comprisespolypropylene fibers. In addition, the mixture of a substantially linearethylene polymer or a homogeneously branched linear ethylene polymerwith a fiber-grade polypropylene resin can result in an impact modifiedrecycle composition which is useful for injection molding and othermolding applications as well as reuse in carpet construction, forexample, as the primary backing material or as a blend component of theadhesive backing material polymer composition. That is, polyolefinpolymer mixtures can involve sufficiently similar polymer chemistries,compatibilities, and/or miscibilities to permit good recyclabilitywithout having sufficient similarities to permit integral fusion.

[0080] The preferred homogeneously branched ethylene polymer has asingle melting peak between −30° C. and 150° C., as determined usingdifferential scanning calorimetry. The most preferred homogeneouslybranched ethylene polymer for use in the invention is a substantiallylinear ethylene polymer characterized as having

[0081] (a) a melt flow ratio, I₁₀/I₂ ≧5.63,

[0082] (b) a molecular weight distribution, M_(w)/M_(n), as determinedby gel permeation chromatography and defined by the equation:

(M _(w) /M _(n))≦(I ₁₀ /I ₂)−4.63,

[0083] (c) a gas extrusion rheology such that the critical shear rate atonset of surface melt fracture for the substantially linear ethylenepolymer is at least 50 percent greater than the critical shear rate atthe onset of surface melt fracture for a linear ethylene polymer,wherein the linear ethylene polymer has a homogeneously branched shortchain branching distribution and no long chain branching, and whereinthe substantially linear ethylene polymer and the linear ethylenepolymer are simultaneously ethylene homopolymers or interpolymers ofethylene and at least one C₃-C₂₀ ^(a)-olefin and have the same I₂ andM_(w)/M_(n) and wherein the respective critical shear rates of thesubstantially linear ethylene polymer and the linear ethylene polymerare measured at the same melt temperature using a gas extrusionrheometer.

[0084] (d) a single differential scanning calorimetry, DSC, melting peakbetween −30° and 150° C.

[0085] Determination of the critical shear rate in regards to meltfracture as well as other rheology properties such as “rheologicalprocessing index” (PI), is performed using a gas extrusion rheometer(GER). The gas extrusion rheometer is described by M. Shida, R. N.Shroff and L. V. Cancio in Polymer Engineering Science, Vol. 17, No. 11,p. 770 (1977), and in “Rheometers for Molten Plastics” by John Dealy,published by Van Nostrand Reinhold Co. (1982) on pp. 97-99. GERexperiments are performed at a temperature of 190° C., at nitrogenpressures between about 250 and about 5500 psig (about 1.7 and about37.4 MPa) using a 0.0754 mm diameter, 20:1 L/D die with an entranceangle of about 180°. For the substantially linear ethylene polymers usedherein, the PI is the apparent viscosity (in kpoise) of a materialmeasured by GER at an apparent shear stress of 2.15×10⁶ dyne/^(cm2)(2.19×10⁴ kg/m²). The substantially linear ethylene polymer for use inthe invention have a PI in the range of 0.01 kpoise to 50 kpoise,preferably 15 kpoise or less. The substantially linear ethylene polymersused herein also have a PI less than or equal to 70 percent of the PI ofa linear ethylene polymer (either a Ziegler polymerized polymer or ahomogeneously branched linear polymer as described by Elston in U.S.Pat. No. 3,645,992) having an I₂ and M_(w)/M_(n), each within tenpercent of the substantially linear ethylene polymer.

[0086] An apparent shear stress versus apparent shear rate plot is usedto identify the melt fracture phenomena and quantify the critical shearrate and critical shear stress of ethylene polymers. According toRamamurthy in the Journal of Rheology, 30(2), 337-357, 1986, above acertain critical flow rate, the observed extrudate irregularities may bebroadly classified into two main types: surface melt fracture and grossmelt fracture.

[0087] Surface melt fracture occurs under apparently steady flowconditions and ranges in detail from loss of specular film gloss to themore severe form of “sharkskin.” Herein, as determined using theabove-described GER, the onset of surface melt fracture (OSMF) ischaracterized at the beginning of losing extrudate gloss at which thesurface roughness of the extrudate can only be detected by 40×magnification. As described in U.S. Pat. No. 5,278,272, the criticalshear rate at the onset of surface melt fracture for the substantiallylinear ethylene interpolymers and homopolymers is at least 50 percentgreater than the critical shear rate at the onset of surface meltfracture of a linear ethylene polymer having essentially the same I₂ andM_(w)/M_(n).

[0088] Gross melt fracture occurs at unsteady extrusion flow conditionsand ranges in detail from regular (alternating rough and smooth,helical, etc.) to random distortions. For commercial acceptability tomaximize the performance properties of films, coatings and moldings,surface defects should be minimal, if not absent. The critical shearstress at the onset of gross melt fracture for the substantially linearethylene polymers used in the invention, especially those having adensity >0.910 g/cc, is greater than 4×10⁶ dynes/cm². The critical shearrate at the onset of surface melt fracture (OSMF) and the onset of grossmelt fracture (OGMF) will be used herein based on the changes of surfaceroughness and configurations of the extrudates extruded by a GER.

[0089] The homogeneous ethylene polymers used in the present inventionare characterized by a single DSC melting peak. The single melting peakis determined using a differential scanning calorimeter standardizedwith indium and deionized water. The method involves 5-7 mg samplesizes, a “first heat” to about 140° C. which is held for 4 minutes, acool down at 10°/min. to −30° C. which is held for 3 minutes, and heatup at 10° C./min. to 150° C. for the “second heat”. The single meltingpeak is taken from the “second heat” heat flow vs. temperature curve.Total heat of fusion of the polymer is calculated from the area underthe curve.

[0090] For polymers having a density of 0.875 g/cc to 0.910 g/cc, thesingle melting peak may show, depending on equipment sensitivity, a“shoulder” or a “hump” on the low melting side that constitutes lessthan 12 percent, typically, less than 9 percent, and more typically lessthan 6 percent of the total heat of fusion of the polymer. Such anartifact is observable for other homogeneously branched polymers such asExact™ resins and is discerned on the basis of the slope of the singlemelting peak varying monotonically through the melting region of theartifact. Such an artifact occurs within 34° C., typically within 27°C., and more typically within 20° C. of the melting point of the singlemelting peak. The heat of fusion attributable to an artifact can beseparately determined by specific integration of its associated areaunder the heat flow vs. temperature curve.

[0091] Whole polymer product samples and individual polymer componentsare analyzed by gel permeation chromatography (GPC) on a Waters 150 hightemperature chromatographic unit equipped with three mixed porositycolumns (Polymer Laboratories 10³, 10⁴, 10⁵ and 10⁶ Å), operating at asystem temperature of 140° C. The solvent is 1,2,4-trichlorobenzene,from which 0.3 percent by weight solutions of the samples are preparedfor injection. The flow rate is 1.0 milliliters/minute and the injectionsize is 100 microliters.

[0092] The molecular weight determination with is deduced by usingnarrow molecular weight distribution polystyrene standards (from PolymerLaboratories) in conjunction with their elution volumes. The equivalentpolyethylene molecular weights are determined by using appropriateMark-Houwink coefficients for polyethylene and polystyrene (as describedby Williams and Ward in Journal of Polymer Science, Polymer Letters,Vol. 6, p. 621, 1968) to derive the following equation:

M _(polyethylene) =a*(M _(polystyrene))^(b).

[0093] In this equation, a=0.4316 and b=1.0. Weight average molecularweight, M_(w), and number average molecular weight, M_(n), arecalculated in the usual manner according to the following formula:M_(j)=(S w_(i)(M_(i) ^(j)))^(j); where w_(i) is the weight fraction ofthe molecules with M_(i) eluting from the GPC column in fraction i andj=1 when calculating M_(w) and j=−1 when calculating M_(n).

[0094] The molecular weight distribution (M_(w)/M_(n)) for thesubstantially linear ethylene polymers and homogeneous linear ethylenepolymers used in the present invention is generally from about 1.8 toabout 2.8.

[0095] However, substantially linear ethylene polymers are known to haveexcellent processability, despite having a relatively narrow molecularweight distribution. Unlike homogeneously and heterogeneously branchedlinear ethylene polymers, the melt flow ratio (I₁₀/I₂) of substantiallylinear ethylene polymers can be varied essentially independently oftheir molecular weight distribution, M_(w)/M_(n).

[0096] Suitable homogeneously branched ethylene polymers for use in thepresent invention include interpolymers of ethylene and at least one^(a)-olefin prepared by a solution, gas phase or slurry polymerizationprocess or combinations thereof. Suitable ^(a)-olefins are representedby the following formula:

CH₂═CHR

[0097] where R is a hydrocarbyl radical. Further, R may be a hydrocarbylradical having from one to twenty carbon atoms and as such the formulaincludes C₃-C₂₀ ^(a)-olefins. Suitable ^(a)-olefins for use ascomonomers include propylene, 1-butene, 1-isobutylene, 1-pentene,1-hexene, 4-methyl-1-pentene, 1-heptene and 1-octene, as well as othercomonomer types such as styrene, halo- or alkyl-substituted styrenes,tetrafluoro-ethylene, vinyl benzocyclobutane, 1,4-hexadiene,1,7-octadiene, and cycloalkenes, e.g., cyclopentene, cyclohexene andcyclooctene. Preferably, the comonomer will be 1-butene, 1-pentene,4-methyl-1-pentene, 1-hexene, 1-heptene, 1-octene, or mixtures thereof,as adhesive backing materials comprised of higher ^(a)-olefins will haveespecially improved toughness. However, most preferably, the comonomerwill be 1-octene and the ethylene polymer will be prepared in a solutionprocess.

[0098] The density of the substantially linear ethylene polymer orhomogeneously branched linear ethylene polymer, as measured inaccordance with ASTM D-792, does not exceed 0.92 g/cc, and is generallyin the range from about 0.85 g/cc to about 0.92 g/cc, preferably fromabout 0.86 g/cc to about 0.91 g/cc, and especially from about 0.86 g/ccto about 0.90 g/cc.

[0099] The molecular weight of the homogeneously branched linearethylene polymer or substantially linear ethylene polymer isconveniently indicated using a melt index measurement according to ASTMD-1238, Condition 190° C./2.16 kg (formerly known as “Condition (E)” andalso known as I₂). Melt index is inversely proportional to the molecularweight of the polymer. Thus, the higher the molecular weight, the lowerthe melt index, although the relationship is not linear. The melt indexfor the homogeneously branched linear ethylene polymer or substantiallylinear ethylene polymer is generally from about 1 grams/10 minutes (g/10min) to about 500 g/10 min, preferably about 2 g/10 min. to about 300g/10 min., more preferably from about 5 g/10 min to about 100 g/10 min.,especially from about 10 g/10 min. to about 50 g/10 min., and mostespecially about 25 to about 35 g/10 min.

[0100] Another measurement useful in characterizing the molecular weightof the homogeneous linear ethylene polymer or the substantially linearethylene polymer is conveniently indicated using a melt indexmeasurement according to ASTM D-1238, Condition 190° C./10 kg (formerlyknown as “Condition (N)” and also known as I₁₀). The ratio of the I₁₀and the I₂ melt index terms is the melt flow ratio and is designated asI₁₀/I₂. For the substantially linear ethylene polymer, the I₁₀/I₂ ratioindicates the degree of long chain branching, i.e., the higher theI₁₀/I₂ ratio, the more long chain branching in the polymer. The I₁₀/I₂ratio of the substantially linear ethylene polymer is at least 6.5,preferably at least 7, especially at least 8. The I₁₀/I₂ ratio of thehomogeneously branched linear ethylene polymer is generally less than6.3.

[0101] Preferred ethylene polymers for us in the present invention havea relative low modulus. That is, the ethylene polymer is characterizedas having a 2% secant modulus less than 24,000 psi (163.3 MPa),especially less than 19,000 psi (129.3 MPa) and most especially lessthan 14,000 psi (95.2 MPa), as measured in accordance with ASTM D790.

[0102] Preferred ethylene polymers for use in the a present inventionare substantially amorphous or totally amorphous. That is, the ethylenepolymer is characterized as having a percent crystallinity less than 40percent, preferably less than 30 percent, more preferably less than 20and most preferably less than 10 percent, as measured by differentialscanning calorimetry using the equation percentcrystallinity=H_(f)/292*100, where Hf is the heat of fusion inJoules/gram.

[0103] The homogeneously branched ethylene polymer can be used alone orcan be blended or mixed with one or more synthetic or natural polymericmaterial. Suitable polymers for blending or mixing with homogeneouslybranched ethylene polymers used in the present invention include, butare not limited to, another homogeneously branched ethylene polymer, lowdensity polyethylene, heterogeneously branched LLDPE, heterogeneouslybranched ULDPE, medium density polyethylene, high density polyethylene,grafted polyethylene (e.g. a maleic anhydride extrusion graftedheterogeneously branched linear low polyethylene or a maleic anhydrideextrusion grafted homogeneously branched ultra low densitypolyethylene), ethylene acrylic acid copolymer, ethylene vinyl acetatecopolymer, ethylene ethyl acrylate copolymer, polystyrene,polypropylene, polyester, polyurethane, polybutylene, polyamide,polycarbonate, rubbers, ethylene propylene polymers, ethylene styrenepolymers, styrene block copolymers, and vulcanates.

[0104] The actual blending or mixing of various polymers may beconveniently accomplished by any technique known in the art including,but not limited to, melt extrusion compounding, dry blending, rollmilling, melt mixing such as in a Banbury mixer and multiple reactorpolymerization. Preferred blends or mixtures include a homogeneouslybranched ethylene polymer and a heterogeneously branched ethylene^(a)-olefin interpolymer wherein the ^(a)-olefin is a C₃-C₈ ^(a)-olefinprepared using two reactors operated in parallel or in series withdifferent catalyst systems employed in each reactor. Multiple reactorpolymerizations are described in copending applications U.S. Ser. No.08/544,497, filed Oct. 18, 1995 and U.S. Ser. No. 08/327,156, filed Oct.21, 1994. However, preferred multiple reactor polymerizations comprisenon-adiabatic solution loop reactors as described in provisionalapplications U.S. Ser. No. 60/014696 and U.S. Ser. No. 60/014705, bothfiled Apr. 1, 1996.

[0105] A range of resin properties, processing conditions and equipmentconfigurations have been discovered for extrusion coatable carpetbacking systems that deliver performance similar or better thanincumbent latex and polyurethane systems.

[0106]FIG. 1 is an illustration of a tufted carpet 10. The tufted carpet10 is made of a primary backing material 11 with yarn 12 tuftedtherethrough; an adhesive backing material 13 which is in intimatecontact with the back surface of the primary backing material 11,substantially encapsulates the yarn 12 and penetrates the yarn 12 andbinds individual carpet fibers; and an optional secondary backingmaterial 14 applied to the back surface of the adhesive backing material13.

[0107]FIG. 2 is an illustration of an extrusion coating line 20 formaking a carpet 70. The line 20 includes an extruder 21 equipped with aslot die 22, a nip roll 24, a chill roll 23, an exhaust hood 26, agreige good feeder roll 28 and a pre-heater 25. As illustrated, the niproll is preferably equipped with a vacuum slot 29 to draw a vacuumacross about 60 degrees or about 17 percent of its circumference and isequipped with a vacuum pump 27. The slot die 22 dispenses an adhesivebacking material in the form of a semi-molten or molten polymer web 30onto greige good 40 with the polymer web 30 towards the chill roll 23and the greige good 40 towards the optional vacuum nip roll 24. Asillustrated, an optional secondary backing material 50 is applied ontothe polymer web 30. The point where the nip roll 24 and the chill roll23 are closest to one another is referred to as the nip 60.

[0108] The present invention is useful in producing carpets with faceyarn made from various materials including, but not limited to,polypropylene, nylon, wool, cotton, acrylic, polyester andpolytrimethylenetheraphthalate (PTT). However, again because one of theobjects of the present invention is to provide a recyclable carpet suchas, for example, a 100% polyolefin carpet, the most preferred yarncomprises a polyolefin, more preferably, polypropylene. Most preferably,the yarn used in the present invention is an air entangled 2750 denierpolypropylene yarn such as that produced by Shaw Industries, Inc. andsold under the designation “Permacolor 2750 Type 015.”

[0109] The preferred primary backing material comprises a polyolefin,more preferably polypropylene. Most preferably, the primary backingmaterial is a slit film polypropylene sheet such as that sold by AMOCOor Synthetic Industries. Alternatively, other types of primary backingmaterials, such as non-woven webs, can also be used. Although othermaterials, such as polyesters or polyamides can be used for the primarybacking material, it is preferred to use a polyolefin so that theobjective of producing a carpet made entirely from polyolefins isachieved. In addition, polypropylene primary backing materials aretypically lower in cost.

[0110] The method of tufting or needle-punching the yarn is not deemedcritical to the present invention. Thus, any conventional tufting orneedle-punching apparatus and stitch patterns can be used. Likewise, itdoes not matter whether tufted yarn loops are left uncut to produce aloop pile; cut to make cut pile; or cut, partially cut and uncut to makea face texture known as tip sheared.

[0111] After the yarn is tufted or needle-punched into the primarybacking material, the greige good is typically rolled up with the backside of the primary backing material facing outward and held until it istransferred to the backing line.

[0112] In a preferred embodiment, the greige good is scoured or washedbefore it has an adhesive backing material extruded thereon. Inparticular, yarn that is tufted or needle-punched to make carpet oftenhas varying quantities of processing materials, most commonly oily orwaxy chemicals, known as spin-finish chemicals, remaining thereon fromthe yam manufacturing processes. It has been found to be preferable toremove or displace all or substantially all of these processingmaterials prior to extruding the adhesive backing material onto the backsurface of the primary backing material. A preferred scouring or washingmethod includes passing the greige good through a bath containing anaqueous detergent solution at about 64 to about 70° C. (e.g., 67° C.).Suitable detergents include, but are not limited to, STA which isavailable from American Emulsions. After the detergent washingprocessing step, the greige good is dried or preheated. Drying can beaccomplished at a temperature of about 108° C. to about 112° C. (e.g.,110° C.) for about 1.8 to about 2.2 minutes (e.g., 2 minutes).

[0113] Another preferred scouring or washing method includes using a wetvacuum cleaner system that initially dispenses ambient temperature wateror heated water (either optionally containing a detergent or cleaningsolution) onto the primary backing material side of the greige good andthen sequentially vacuums up the water and retained amounts ofprocessing materials. The wet vacuum system is suitably adapted with adispensing and vacuum wand or head such that the entire width of thegreige good can be wet vacuumed at least once on a continuous extrusioncoating line. After the wet vacuuming processing step, the greige goodis suitably dried and/or preheated. Suitable detergents, cleaningsolutions or cleaning concentrates for use in a wet vacuuming methodincludes, but is not limited to, aqueous alkaline solutions, forexample, those consisting of ethylene diamine tetracetic acidtetrasodium salt. One suitable wet vacuum cleaner system is theRinsevac™ carpet cleaning system and one suitable cleaning concentrateis the Rinsevac™ Professional Carpet Cleaner both supplied by BlueLustre Products, Inc., Indianapolis, In.

[0114] Other suitable methods of the present invention for scouring orwashing processing materials, adaptable to an extrusion coating linesuch as, for example, the one illustrated in FIG. 2, include steamcleaning, flashing at elevated temperatures and/or under vacuum, andsolvent chemical washing of the greige good.

[0115] It is also contemplated that the use of polyolefin waxes (ratherthan conventional organic and mineral oils) as processing materialswould allow improved adhesive backing material performance in itself orat least less demanding scouring or washing requirements. Nevertheless,practitioners will find that scouring or washing requirements may varywith the amount and specific type of processing materials present. Thatis, higher quantities of process materials and/or higher molecularprocessing materials may require more stringent scouring and washingtechniques such as, for example, multiple washing and drying steps usingconcentrated washing solutions based on softened or deionized water.Practitioners will also recognize that scouring and washing requirementsfor effectively removing or displacing processing materials may be moreextensive than ordinary washings or other cleaning procedures performedfor cosmetic or decorative purposes or performed to simply remove loosefibers, primary backing material or other debris that ordinarily resultfrom tufting, needle-punch and/or cutting operations.

[0116] In another aspect of the present invention, the greige good iscoated with an aqueous pre-coat material, either as a final backing orpreferably before an adhesive backing material is extruded thereon. Theparticles in this dispersion can be made from various polyolefinmaterials such as ethylene acrylic acid (EAA), ethylene vinyl acetate(EVA), polypropylene or polyethylene (e.g., low density polyethylene(LDPE), linear low density polyethylene (LLDPE) or substantially linearethylene polymer, or mixtures thereof). Presently, polyethyleneparticles are preferred. Most preferably, the polyethylene particles arethose sold by Quantum USI Division under the designation “MicrotheneFN500.”

[0117] Preferably, the polyolefin particles are present in an amountbetween about 10 and 75 percent by weight of the dispersion, morepreferably between about 20 and about 50 percent, and most preferablybetween about 25 and about 33 percent.

[0118] The particle size of the polyolefin particles is important bothto ensure that a good dispersion is achieved and also to ensure that thepolyolefin particles penetrate the yarn and primary backing so as toprovide good abrasion resistance. Preferably, the average particle sizeof the polyolefin particles is between about 1 and about 1000 microns,and more preferably between about 5 and 40 microns. The most preferredpolyethylene particles referred to above have an average particle sizeof about 18 to about 22 microns (e.g., 20 microns).

[0119] Preferably, the polyolefin particles have a Vicat softening point(as measured in accordance with ASTM D1525) between about 50 and about100° C., and more preferably between about 75 and 100° C. The mostpreferred polyethylene particles referred to above have a softeningpoint of about 80° to about 85° C. (e.g., 83° C.).

[0120] When polypropylene particles are used, they preferably have amelt flow (ASTM D-1238 Condition 210/2.16) between about 1 to about 80,most preferably between about 60 and about 80. When polyethyleneparticles are used, they preferably have an I₂ melt index (ASTM D-1238Condition 190/2.16) between about 1 and about 100 g/10 minutes, and morepreferably between about 20 and about 25 g/10 minutes. The mostpreferred polyethylene particles referred to above have an I₂ melt indexof t 22 g/10 minutes.

[0121] Ethylene acrylic acid (EAA) may be used for the polyolefinparticles, preferably in combination with polyethylene or polypropyleneparticles. It has been found that EAA can increase the adhesion of thepre-coat to the yarn and primary backing, as well as to a thermoplasticsheet extruded thereon.

[0122] The aqueous dispersion preferably contains other ingredients. Forexample, a surfactant is preferably included to aid in keeping thepolyolefin particles dispersed. Suitable surfactants are nonionic,anionic, cationic and fluorosurfactants. Preferably, the surfactant ispresent in an amount between about 0.01 and about 1 weight percent basedon the total weight of the dispersion. More preferably, the surfactantis anionic. Most preferably, the surfactant is one sold by Ciba Geigyunder the designation “Igepal C0430” and is present at 0.1 weightpercent based on the total weight of the dispersion.

[0123] A thickener is also preferably included to provide a suitableviscosity to the dispersion. Preferably, the thickener is one selectedfrom the group consisting of sodium and ammonium salts of polyacrylicacids and is present in an amount between about 0.1 and about 2 weightpercent based on the total weight of the dispersion. Most preferably,the thickener is a salt of a polyacrylic acid such as that sold by SunChem International under the designation “Print Gum 600” and is presentat about 0.8 weight percent based on the total weight of the dispersion.

[0124] Preferably, the viscosity of the dispersion measured on aBrookfield RVT viscometer is between about 3000 cP (centipoises) at 20rpm with a No. 5 spindle and about 50,000 cP at 2.5 rpm with a No. 5spindle measured at 23° C. Most preferably, the viscosity of thedispersion is between about 10,000 and 20,000 cP at 2.5 rpm with a No. 5spindle.

[0125] In addition, the dispersion preferably includes a defoamingagent. Preferably, the defoaming agent is a non-silicone defoaming agentand is present in an amount between about 0.01 and about 1.0 weightpercent based on the total weight of the dispersion. Most preferably,the defoamer is one such as that sold by LENMAR Chemical Corporationunder the designation “MARFOAM N-24A” and is present at about 0.1 weightpercent based on the total weight of the dispersion.

[0126] Preferably, the aqueous dispersion further includes a dispersionenhancer, such as fumed silica which has been found to act as acompatibilizer for the dispersion, thus allowing the use of largerpolyolefin particles. Preferably, the fumed silica is present at betweenabout 0.1 and about 0.2 weight percent based on the total weight of thedispersion. Most preferably, the fumed silica is one such as that soldby DeGussa under the designation “Aerosil 300.”

[0127] The aqueous dispersion of polyolefin particles can be made up invarious ways. Preferably, the ingredients are added to the water in thefollowing order: surfactant, defoamer, polyolefin, thickener. Themixture is then agitated in a homogenous mixer, preferably with highshear mixing, until all lumps have dispersed, typically for about 8 toabout 12 minutes (e.g., 10 minutes).

[0128] The dispersion can be applied to the carpet in various ways. Forexample, the dispersion can be applied directly, such as with a rollover roller applicator, or a doctor blade. Alternatively, the dispersioncan be applied indirectly, such as with a pan applicator. Preferably, aroll over roller applicator is used with the top roller turning at about22 to about 27 percent of line speed (e.g., 25 percent of line speed).

[0129] The amount of dispersion applied and the concentration of theparticles can be varied depending on the desired processing and productparameters. Preferably, the amount of dispersion applied and theconcentration of the particles are selected so as to apply between about4 and about 12 ounces per square yard (OSY) (about 141.5 and about 424.4cm³/m²) of carpet. Most preferably, this is achieved by using adispersion containing about 50 weight percent polyolefin particles(based on the total weight of the dispersion) and applying between about8 and about 10 OSY (about 283 and about 353.7 cm³/m²) of the dispersion.

[0130] After application of the dispersion, heat is applied to the backside of the primary backing so as to dry the dispersion and to at leastpartially melt the particles. As a result, the loops of yarn are fixedto the primary backing. Preferably, the heat is applied by passing theproduct through an oven. Such an oven is preferably set at a temperaturebetween about 100 and about 150° C. and the product spends between about2 and about 5 minutes passing through the oven. Also, since the objectis to at least partially melt the particles, the temperature of the ovenis set at between about 5 and about 75° C. above the Vicat softeningpoint of the polyolefin particles.

[0131] After treatment with the dispersion of polyolefin particles, thecarpet may be used as is or, more preferably, may have an additionalbacking applied thereto. Additional backings car be applied by variousmethods with the preferred method, as described above, involving the useof an extruded sheet of a thermoplastic material, preferably thehomogeneously branched ethylene polymer described above, onto which aconventional secondary backing is laminated. In particular, a moltenthermoplastic material is preferably extruded through a die so as tomake a sheet which is as wide as the carpet. The molten, extruded sheetis applied to the back side of the primary carpet backing. Since thesheet is molten, the sheet will conform to the shape of the loops ofyarn and further serve to fix the loops in the primary backing.

[0132] Extrusion coating configurations include a monolayer T-type die,single-lip die coextrusion coating, dual-lip die coextrusion coating,and multiple stage extrusion coating. Preferably, the extrusion coatingequipment is configured to apply a total coating weight of between about4 and about 30 ouncesyd² (OSY) (about 141.5 and about 1061.1 cm³/m²),with between about 18 OSY (about 636.7 cm³/m²) and about 22 OSY (about778.1 cm³/m²), e.g., 20 OSY, (707.4 cm³/m²) being most preferred.

[0133] Measured another way, the thickness of an unexpanded, collapsedextrusion coated adhesive backing material is in the range from about 6to about 80 mils, preferably from about 10 to about 60 mils (about 0.25to about 1.52 mm), more preferably from about 15 to about 50 mils (about0.38 to about 1.27 mm), and most preferably from about 20 to about 40mils (about 0.51 to about 1.02 mm).

[0134] The line speed of the extrusion process will depend on factorssuch as the particular polymer being extruded, the exact equipment beingused, and the weight of polymer being applied. Preferably, the linespeed is between about 18 and about 250 ft./min. (about 5.5 and about76.2 m/min.), more preferably between about 80 and about 220 ft./min.(about 24.4 and about 67.1 m/min.), most preferably between about 100and about 200 ft./min. (about 30.5 and about 61 m/min.).

[0135] The extrusion coating melt temperature principally depends on theparticular polymer being extruded. When using the most preferredsubstantially linear polyethylene described above, the extrusion coatingmelt temperature is greater than about 450° F. (232° C.), preferablygreater than or equal to about 500° F. (about 260° C.), or is betweenabout 450° (about 232° C.) and about 650° F. (about 343° C.), morepreferably between about 475° (about 246° C.) and about 600° F. (about316° C.), most preferably between about 500° and about 550° F. (about260° and about 288° C.).

[0136] Preferably, two layers of resin, each layer comprising adifferent resin, are extruded with the layer applied directly onto thebackside of the primary backing material (first layer) having a highermelt index than the second layer which is applied onto the backside ofthe first layer. Since it is the first layer which is relied on toencapsulate and penetrate the yarn, this layer should have a melt indexhigh enough (melt viscosity low enough) to promote encapsulation andpenetration of the yarn. The second layer, which is generally not reliedon to encapsulate and penetrate the yarn, may be used either as thebottom surface of the carpet or to facilitate the application of anoptional secondary backing material. For both of these uses, it ispreferred to have a lower melt index to provide higher strength aftercooling. In addition, because it is not relied on for encapsulating orpenetrating the fiber bundles, a resin of lower quality and/or lesstightly controlled properties may be used in the second layer. In apreferred embodiment, the second layer is a recycled feedstock.

[0137] Also, the first and second layers may consist of differentpolymer chemistries or compositions. For example, the first layer can becomprised of an adhesive polymer (as an additive or as the compositionof the entire layer) such as, but not limited to, an ethylene vinylacetate copolymer, an ethylene acrylic acid copolymer or a maleicanhydride/ethylene polymer graft (preferably, a substantially linearethylene polymer/maleic anhydride extrusion graft or a high densitypolyethylene/maleic anhydride extrusion graft) and the second layer canbe comprised of a non-polar polymer such as a homogeneously branchedethylene polymer, a low density polyethylene or ultra low densitypolyethylene. Alternately, the first layer can be comprised of anon-polar polymer and the second layer can be comprised of an adhesivepolymer.

[0138] Preferably, the first layer has an I₂ melt index between about 30and about 175 g/10 min. and the second layer has an I₂ melt indexbetween about 1 and about 70 g/10 min. Most preferably, the first layerhas an I₂ melt index between about 30 and about 70 g/10 min and thesecond layer has an I₂ melt index between about 10 and about 30 g/10min.

[0139] It is also preferred to extrude two layers of a single polymercomposition so as to have greater control over the thickness or weightof the resin applied to the carpet. In alternative embodiments, three ormore layers of the resin can be extruded on the back surface of theprimary backing material to achieve even higher coat weights and/or toobtain a more gradual transition between the first and last layerapplied. Preferably, a dual lip die is used to apply two layers.Alternatively, two or more extrusion stations or a single lipcoextrusion die can be used to apply these two or more layers.

[0140] Another aspect of the present invention is the use of modifiedhomogeneously branched ethylene polymers. In particular, in certainaspects of the invention the at least one homogeneously branchedethylene polymer that is employed as the adhesive backing material,primary backing material or yarnpreferably as the adhesive backingmaterial, is modified by the addition of at least one adhesive polymericadditive. Suitable adhesive polymeric additives include polymer productscomprised of (1) one or more ethylenically unsaturated carboxylic acids,anhydrides, alkyl esters and half esters, e.g., acrylic acid,methacrylic acid, maleic acid, maleic anhydride, itaconic acid, fumaricacid, crotonic acid and citraconic acid, citraconic anhydride, succinnicacid, succinnic anhydride, methyl hydrogen maleate, and ethyl hydrogenmaleate; esters of ethylenically unsaturated carboxylic acids, e.g.,ethyl acrylate, methyl methacrylate, ethyl methacrylate, methylacrylate, isobutyl acrylate, and methyl fumarate; unsaturated esters ofcarboxylic acids, e.g., vinyl acetate, vinyl propionate, and vinylbenzoate; and ethylenically unsaturated amides and nitriles e.g.,acrylamide, acrylonitrile, methacrylonitrile and fumaronitrile; and (2)one or more ethylenically unsaturated hydrocarbon monomers such asaliphatic ^(a)-olefin monomers, e.g., ethylene, propylene, butene-1 andisobutene; conjugated dienes, e.g., butadiene and isoprene; andmonovinylidene aromatic carbocyclic monomers, e.g. styrene,a-methylstyrene, toluene, and t-butylstyrene. Suitable adhesivepolymeric additives can be conveniently prepared by known techniquessuch as, for example, by interpolymerization or by a polymerizationprocedure followed by a chemical or extrusion grafting procedure.Suitable grafting techniques are described in U.S. Pat. Nos. 4,762,890;4,927,888; 4,230,830; 3,873,643; and 3,882,194.

[0141] Preferred adhesive polymeric additives for use in the presentinvention are maleic anhydride grafts wherein maleic anhydride isgrafted onto an ethylene polymer at a concentration of about 0.1 toabout 5.0 weight percent, preferably about 0.5 to about 1.5 weightpercent. The use of ethylene polymer/maleic anhydride grafts as adhesivepolymeric additives in the present invention significantly improves theperformance and operating window of extrusion coated homogeneouslybranched ethylene polymers as the adhesive backing material, especiallyfor polar polymer such as for example, but not limited to, nylon andpolyester faced carpets. The improvement pertained to substantiallyhigher comparative abrasion resistance and tuft bind strength. Theimprovement was surprising in that graft adhesives are generally knownto require extended molten or semi-molten contact times for improvedperformance and function as interlayer adhesives for films and coatingswhere there is a continuous substrate as opposed to the discontinuousinterface existent in carpet construction.

[0142] Preferred ethylene polymers for use as the grafted host polymerinclude low density polyethylene (LDPE), high density polyethylene(HDPE), heterogeneously branched linear low density polyethylene(LLDPE), homogeneously branched linear ethylene polymers andsubstantially linear ethylene polymers. Preferred host ethylene polymershave a polymer density greater than or equal to 0.915 g/cc and mostpreferably greater than or equal to 0.92 g/cc. Substantially linearethylene polymers and high density polyethylene are the preferred hostethylene polymers.

[0143] In this aspect of the present invention, the adhesive polymericadditive is added to the homogeneously branched ethylene polymer at alevel in the range of from about 0.5 to about 30 weight percent,preferably from about 1 to about 20 weight percent, more preferably fromabout 5 to about 15 weight percent based on the total weight of thepolymer. For the preferred ethylene polymer maleic anhydride grafts,additions should provide a final maleic anhydride concentration in therange of from about 0.01 to about 0.5 weight percent, preferably fromabout 0.05 to about 0.2 weight percent based on the total weight of thepolymer.

[0144] Auxiliary equipment such as a pre-heater can be used. Inparticular, a heater, such as a convection oven or infrared panels canbe used to heat the back of the greige good before the adhesive backingmaterial is extruded thereon. In doing so, it has been found that theencapsulation and penetration of the yarn bundles can be enhanced.Preferably, the pre-heater is an infrared unit set at between about 200and about 1500° C. and the greige good is exposed to this heating forbetween about 3 and about 30 seconds. Most preferably, the heater is setat about 1000° C. and the greige good is exposed to this heating forabout 5 to about 7 seconds (e.g., 6 seconds).

[0145] In addition to or as an alternative to pre-heating, the processof the invention may also employ a post-heat soaking process step tolengthen the molten time for the adhesive backing material to therebyimprove the encapsulation and penetration of the yarn or fiber bundlesby the adhesive backing material. Preferably, after the adhesive backingmaterial is applied to the greige good, it is heated by a convectionoven or infrared radiation at a temperature between about 200 and about1500° C. for between about 3 and 30 seconds, most preferably at 1000° C.for about 5 to about 7 seconds (e.g., 6 seconds).

[0146] As another piece of auxiliary or optional equipment, a vacuum niproll can be used to draw the adhesive backing material extrudate (i.e.,semi-molten or molten polymer web) onto the greige good. In a properlyconfigured extrusion coating operation, the pile face of the greige goodis positioned towards the vacuum nip roll and the polymer web is drawdown onto the back surface of the primary backing material of the greigegood. Vacuum nip roll 24 (which is illustrated in FIG. 2 and isavailable from Black Clawson Corporation) is suitable for vacuum drawingthe adhesive backing material web. Vacuum nip roll 24 can be adaptedfrom a conventional nip roll wherein a portion of the hollow internal ofthe roll is partitioned, dedicated and coupled to a external vacuum pump27 to provide a vacuum surface. The surface of the vacuum portion isperforated but machined flush and continuously with the remainingsurface of the roll. Suitable vacuum nip rolls can have a complete 360degree vacuum surface; however, a vacuum surface of from about 10 toabout 180 degrees is preferred, most preferably about 60 degrees. Toeffectively draw the adhesive backing material web onto the greige goodand maximize to the penetration of the yarn or fiber bundles, the vacuumis set to greater than 15 inches of H₂O (3.7 Pa), preferably greaterthan or equal to 25 inches of H₂O (6.1 Pa) and more preferably greaterthan or equal to 40 inches of H₂O (9.8 Pa), or from between about 15 andabout 50 inches of H₂O (about 3.7 and about 12.3 Pa), preferably frombetween about 20 and about 45 (about 4.9 and about 11.1 Pa).

[0147] The length of time the greige good is actually subjected to thevacuum will primarily depend on the extrusion coating line speed and theextent of draw on the adhesive backing material web will largely dependon the level of vacuum and the porosity of the greige good. As such,higher vacuum levels will be required for higher extrusion coating linespeeds and/or denser greige good to effectively the draw the adhesivebacking material.

[0148] In addition to or as an alternative to a vacuum nip roll, a highpressure positive air device such as an air blade or knife can also beused to force the adhesive backing material web onto the back surface ofthe primary backing material. Preferably, the positive air pressuredevice is set to provide an air pressure greater than 20 psi (0.14 MPa),preferably greater than or equal to 40 psi (0.27 MPa), more preferablygreater than or equal to 60 psi (0.41 MPa), or between about 20 andabout 120 psi (about 0.14 and about 0.82 MPa), most preferably betweenabout 30 and about 80 psi (about 0.20 and about 0.54 MPa) Preferably,the positive air pressure device is positioned at the extrusion coatingnip, extends across the entire width of the polymer web and ispositioned behind the polymer web towards the chill roll so to force thepolymer web onto the greige good and press the polymer web into the yarnor fiber bundles.

[0149] The extruded polymer(s) can either be used neat, or can have oneor more additive included. A preferred additive is an inorganic filler,more preferably, an inorganic filler with a high heat content. Examplesof such fillers include, but are not limited to, calcium carbonate,aluminum trihydrate, talc, barite. High heat content fillers arebelieved to be advantageous in the invention because such fillers allowthe extrudate to remain at elevated temperatures longer with thebeneficial result of providing enhanced encapsulation and penetration.That is, normally fillers are added to carpet backing materials tomerely add bulk (i.e. as extenders) or to impart insulating and sounddampening characteristics. However, we have found that inorganic mineralfillers that have high heat contents surprisingly improve yarnencapsulation and penetration which in turn improves the performance ofthe abrasion resistance and tuft bind strength of extrusion coatedcarpet samples.

[0150] Preferably, a high heat content filler is added at a level ofbetween about 1 and about 75 weight percent of the total extrudate, morepreferably between about 15 and about 60 weight percent and mostpreferably between about 20 weight percent and 50 weight percent. Suchfillers will have a specific heat content of greater than or equal to0.4 cal-cc/° C. (1.8 Joules-cc/° C.), preferably greater than or equalto 0.5 cal-cc/° C. (2 Joules-cm³/° C.), more preferably greater than orequal to 0.6 cal-cc/° C. (2.5 Joules-cm³/° C.), and most preferablygreater than or equal to about 0.7 cal-cc/° C. (2.9 Joules-cm³/° C.).Representative examples of high heat content fillers for use in thepresent invention include, but are not limited to, limestone (primarilyCaCO₃), marble, quartz, silica, and barite (primarily BaSO₄). The highheat content fillers should be ground or precipitated to a size that canbe conveniently incorporated in an extrusion coating melt stream.Suitable particle sizes range from about 1 to about 50 microns.

[0151] If a foamed backing is desired on the carpet, a blowing agent canbe added to the adhesive backing material and/or the optional secondarybacking material. If used, the blowing agents are preferablyconventional, heat activated blowing agents such as azodicarbonamide,toluene sulfonyl semicarbazide, and oxy bis(benzene sulfonyl) hydrazide.The amount of blowing agent added depends on the degree of foamingsought. A typical level of blowing agent is between about 0.1 and about1.0 weight percent.

[0152] Implosion in the present invention is accomplished by restrictingexpansion of the adhesive backing material in the direction opposite theprimary backing material during activation of the implosion agent suchthat the molten polymer is forced into the interior and free space ofthe yarn or fiber bundles. An imploded adhesive backing material willhave a collapsed, non-expanded matrix (relative to a foamed backing) andbe of essentially the same thickness (measured from the plane of theback surface of the primary backing material) as would be the casewithout the use of the implosion agent. That is, the adhesive backingmaterial layer would be characterized as not being expanded by theimplosion agent.

[0153] The implosion agent is selected and formulated into the adhesivebacking material and extrusion conditions are set such that theactivation of the implosion agent occurs at the instant of nip while theadhesive backing material is still semi-molten or molten. With improvedyarn penetration accomplished with the use of an implosion agent, thecarpet will exhibit comparatively improved abrasion resistance. Thus,the use of an implosion agent can allow the use of polymer compositionshaving lower molecular weights to provide improved extrusion coatabilityyet maintain higher abrasion resistance (i.e., comparable to adhesivebacking materials based on higher molecular weight polymercompositions). An effective amount of implosion agent would be betweenabout 0.1 and about 1.0 weight percent based on the weight of theadhesive backing material.

[0154] Conventional blowing agents or any material that ordinarilyfunctions as a blowing agent can be used as an implosion agent in thepresent invention providing expansion of the adhesive backing materialmatrix is suitably restricted or confined when the material is activatedsuch that molten polymer is forced into the interior and free space ofthe yarn or fiber bundles and there is no substantial expansion of theadhesive backing material as a result of having used the implosionagent. However, preferably, an imploded adhesive backing material willbe characterized as having a closed cell structure that can beconveniently identified by photomicrographs at 50× magnification.

[0155] Other additives can also be included in the adhesive backingmaterial, to the extent that they do not interfere with the enhancedproperties discovered by Applicants. For example, antioxidants such assterically hindered phenols, sterically hindered amines and phospitesmay be used. Suitable antioxidants include Irganox® 1010 from Ciba-Geigywhich is a hindered phenol and Irgafos® 168 from Ciba-Geigy which is aphosphite. Other possible additives include antiblock additives,pigments and colorants, anti-static agents, antimicrobial agents (suchas quaternary ammonium salts) and chill roll release additives (such asfatty acid amides).

[0156] As noted above, and shown in FIG. 2, the carpet of the inventionpreferably also includes a secondary backing material. Preferably, thesecondary backing material is laminated directly to the extrudedlayer(s) while the extrudate is still molten after extrusion coating. Ithas been found that this technique can improve the penetration of theextrusion coating into the primary backing.

[0157] Alternatively, the secondary backing material can be laminated ina later step by reheating and/or remelting at least the outermostportion of the extruded layer or by a coextrusion coating techniqueusing at least two dedicated extruders. Also, the secondary backingmaterial can be laminated through some other means, such as byinterposing a layer of a polymeric adhesive material between theadhesive backing material and the secondary backing material. Suitablepolymeric adhesive materials include, but are not limited to, ethyleneacrylic acid (EAA) copolymers, ionomers and maleic anhydride graftedpolyethylene compositions.

[0158] The material for the secondary backing material can be aconventional material such as the woven polypropylene fabric sold byAMOCO under the designation Action Bac®. This material is a leno weavewith polypropylene monofilaments running in one direction andpolypropylene yarn running in the other. More preferably, the secondarybacking material used with the present invention is a wovenpolypropylene fabric with monofilaments running in both directions. Asuitable example of such a material is sold by Amoco under thedesignation Style 3878. This material has a basis weight of 2 OSY (70.7cm³/m²). This material with monofilaments running in both directions hasbeen found beneficial in providing enhanced dimensional stability to thecarpet.

[0159] In an alternatively preferred embodiment, the secondary backingmaterial is a material known as fiber lock weave or “FLW.” FLW is afabric which includes fibers needle punched into it. Sometimes FLW isused as a primary backing material on a carpet with a low pile weight.In such carpet, the fibers protrude on the pile side so as to help keepthe primary backing material from showing through the pile. However, inthis alternatively preferred embodiment, FLW is used as the secondarybacking material with the needle punched fibers protruding away from thecarpet. Doing so has been found to enhance the adhesion of the carpetwhen installed with a glue-down adhesive. In particular, the surfacearea for contacting the glue-down adhesive is increased and theprotruding fibers help to anchor the carpet backing to the glue-downadhesive.

[0160] Alternatively, the secondary backing material can be a non-wovenfabric. Several types are available, including, but not limited to,spun-bond, wet-laid, melt-blown, and air entangled. As noted above, itis preferred that the secondary backing is made from a polyolefin tofacilitate recycling.

[0161] In an alternatively preferred embodiment, the non-woven fabric isspun-bond polypropylene fabric, such as that available from Don & LowNon-wovens under the name “Daltex.” Typically, spun-bond fabric is madefrom. extruded and air-drawn polymer filaments which are laid downtogether and then point bonded, for example by a heated calendar roll.The basis weight of such a spun-bond secondary backing can be varied,preferably between 35 and 80 grams/m² (gsm) more preferably between 60and 80 gsm. Most preferably, the basis weight is 77-83 gsms (e.g., 80gsm). One factor favoring a higher basis weight for the spun-bond fabricis that the higher basis weight fabric is less likely to be melted whenbrought into contact with the molten extruded backing.

[0162] It has been found that a spun-bond non-woven fabric isadvantageous to use as a secondary backing in the present inventionbecause the porous nature of the fabric increases the surface area ofthe carpet for gluing the carpet to the floor.

[0163] In still another alternatively preferred embodiment, thesecondary backing is a woven polypropylene fabric such as Action Bac®from Amoco which has been enhanced by having 2 OSY (70.7 cm³/m²) ofpolypropylene fibers needle punched onto one side of it. This needlepunched fabric is laminated so as to have the polypropylene fibersembedded within the adhesive backing layer. As a result, the strands ofthe woven polypropylene fabric exposed. This embodiment has been shownto have improved glue down properties as compared to an embodimentwithout the needle punched fibers because, without the needle punchedfibers, the strands of the woven polypropylene fabric are at leastpartially embedded in the adhesive backing layer. As such, the surfacearea for gluing is reduced. It was also noted that the back of thecarpet made in this embodiment was much less abrasive than that foundwith traditional latex backed carpet. The carpet is also more flexiblethan traditional latex backed carpet. Consequently, this embodiment ispreferred for making areas rugs and the like.

[0164] Still other materials can be used for the secondary backing. Forexample, if an integral pad is desired, a polyurethane foam or othercushion material can be laminated to the back side of the carpet. Suchbackings can be used for broadloom carpet as well as for carpet tile.

[0165] The extrusion backed carpet construction and the methodsdescribed herein are particularly suited for making carpet tile. FIG. 6shows a cross-section of a carpet tile 100 made according to the presentinvention. A yarn 103, preferably made of polypropylene, is tufted intoa primary backing 101, which is also preferably made of polypropylene,so as to leave a carpet pile face 104 on top of the primary backing 101and back stitches 105 below the primary backing. Applied to the back ofthe primary backing 101 and the back stitches 105 is an adhesive layer107. Preferably, this adhesive layer is made from a polyolefin. Morepreferably, the adhesive layer is made from the ethylene polymersdescribed in detail above. Most preferably, this adhesive layer 107 ismade from a substantially linear ethylene polymer with the additivesdescribed in Example 194 below.

[0166] In a preferred embodiment of carpet tile, the carpet includedfrom about 5 to about 200 OSY (about 176.8 to about 7,074 cm³/m²) ofextruded adhesive backing. More preferably, the carpet for tile includesfrom about 30 to about 80 OSY (about 1061 to about 2,830 cm³/m²) ofextruded backing, most preferably, 50 OSY (1,768 cm³/m²).

[0167] Preferably, the carpet for carpet tile receives its extrudedbacking in two passes, i.e., to apply two layers of the extrudedbacking. The first pass applies the layer 107 in FIG. 6. Preferably thislayer 107 is between about 2.5 and about 100 OSY (about 88.4 to about3,537 cm³/m²) of the extruded polymer, more preferably between about 15and about 40 OSY (about 530.5 to about 1,415 cm³/m²), and mostpreferably 25 OSY (884 cm³/m²). The second pass adds the layer 111.Preferably the second layer 111 is about 2.5 and about 100 OSY (about88.4 to about 3,537 cm³/m²), more preferably between about 15 and 40 OSY(about 530.5 to about 1,415 cm³/m²), and most preferably 25 OSY (884cm³/m²).

[0168] Applying the extruded backing in two passes allows theopportunity to apply a first and second layer which have differentphysical and/or chemical properties. As noted above, it is sometimespreferable to apply a polymer with a higher melt index adjacent theprimary backing, and a polymer with a lower melt index below that. Inaddition, it can also be preferably to use an extrudate with a lowerfiller content in the layer next to the primary backing and an extrudatewith a higher filler content in the layer below that. In one preferredembodiment, the layer next to the primary backing includes a fillerloading of 30 percent by weight and the layer below that includes afiller loading of 60 percent by weight. The lower filler content isbelieved to provide better penetration of the primary backing and backstitches in the carpet by the extrudate.

[0169] When making carpet tile, it is preferable to embed a layer ofreinforcing material 109 between the first and second layers ofextruding backing. An important property of carpet tile is dimensionalstability, i.e., the ability of the tile to maintain its size andflatness over time. The inclusion of this layer of reinforcing materialhas been found to enhance the dimensional stability of carpet tile madeaccording to this preferred embodiment. Suitable reinforcing materialsinclude dimensionally and thermally stable fabrics such as non-woven orwet-laid fiberglass scrims, as well as woven and non-woven thermoplasticfabrics (e.g. polypropylene, nylon and polyester). Most preferably, thereinforcement layer is a polypropylene non-woven fabric sold by Reemayas “Typar” with a basis weight of 3.5 OSY (124 cm³/m²). Alternatively, apreferred reinforcement layer is a fiberglass scrim sold by ELK Corp. as“Ultra-Mat:” with a basis weight of 1.4 OSY (49.5 cm³/m²).

[0170] The carpet tile may include a secondary backing fabric 113 belowthe second layer of extruded backing 111. Suitable materials for thesecondary backing fabric include those described above. However, it ispresently not preferred to include a secondary backing fabric on carpettile.

[0171]FIG. 7 schematically shows a preferred line 120 for making carpettile according to the present invention. A length of greige good 121,i.e. yarn tufted into a primary backing, is unrolled from the roll 123.The greige good 121 passes over the rollers 125 and 127 with the primarybacking toward the roller 123. Between rollers 125 and 127 is apre-heater 129 as described above.

[0172] An extruder 131 is mounted so as to extrude a sheet 135 of thepolymeric backing through the die 133 onto the back of the greige goodat a point between the roller 127 and the nip roll 141. The exactlocation at which the sheet 135 contacts the greige good can be varieddepending on the line speed and the time desired for the molten polymerto rest on the greige good before passing between the nip roll 141 andthe chill roll 143. At present it is preferred that the sheet 135contact the greige good so as to lie on the greige good for betweenabout 0.5 and about 2 seconds, most preferably about 1 second, beforepassing between the nip roll 141 and the chill roll 143.

[0173] In this preferred depicted embodiment, a scrim of non-wovenpolypropylene 139 is fed from roll 137 so as to contact the chill roll143 at a point just prior to the nip roll 141. As a result, the scrim139 which will act as a reinforcing fabric in the finished carpet tileis laminated to the greige good through the polymer.

[0174] The pressure between the nip roll 141 and the chill roll 143 canbe varied depending on the force desired to push the extruded sheet.Most preferably, there is 60 psi (0.41 MPa) of air pressure pushing therolls together. Also, as described in connection with FIG. 2, it may bedesirable to include a vacuum slot in the nip roll. In addition, a jetof pressurized air may also be used to push the extruded sheet into thecarpet backing.

[0175] The size of the chill roll 143 and the length of time the carpetrolls against it can be varied depending on the level of cooling desiredin the process. Preferably the chill roll 143 is cooled by simplypassing ambient water through it.

[0176] After passing over the chill roll 143, the carpet is brought overrollers 145 and 147 with the carpet pile toward the rollers. A secondextruder 149 extrudes a sheet of polymer 153 through its die 151 on tothe back of the scrim 139. Again the point at which the extruded sheet153 contacts the scrim 139 can be varied as described above.

[0177] At this point, if a secondary backing fabric is desired for thecarpet tile, that fabric can be introduced from a roll similar to thatshown at 137 so as to contact the be laminated to the carpet through theextruded sheet 153 as it passes between the nip roll 155 and the chillroll 153. Such a secondary backing fabric is not currently preferred forcarpet tile construction.

[0178] The carpet passes between the nip roll 155 and the chill roll157. Again, the pressure applied between the two rolls 155 and 157 canbe varied. At present, 60 psi (0.41 MPa) of air pressure is preferablyapplied against the nip roll 155.

[0179] After passing around the chill roll 157, the carpet passes aroundroll 159 and is preferably passed over an embossing roll (not shown) toprint a desired pattern on the back of the carpet.

[0180] While the apparatus shown in FIG. 7 is preferred for making acarpet tile with two layers of extruded backing and a reinforcing fabricin between, the same construction can be made with a single extrusiondie, nip roll and chill roll. In particular, the first layer of extrudedbacking and the reinforcing fabric can be applied in a first passthrough the line after which the carpet is rolled up. The second layerof extruded backing can be applied on top of the reinforcing fabric in asecond pass through the same line after which the carpet is ready to becut into carpet tiles.

[0181] Carpet tile is typically made by producing a length of backedcarpet and then cutting the carpet into the appropriate sized squares.In the United States, the most common size is 18 inches (45.7 cm)square. In the rest of the world, the most common size is 50 cm square.

[0182] In still another alternative embodiment, a pressure sensitiveadhesive is applied to the bottom surface of the backed carpet and arelease sheet is included. In this way, a “peel and stick” carpet isproduced. This is particularly beneficial when the carpet is to be cutinto tiles. Examples of suitable pressure sensitive adhesives includeethylene vinyl acetate copolymers and substantially linear ethylenepolymers formulated with tackifiers and polymeric waxes. The releasesheet can be made from conventional polymers and/or paper products.Preferably, the release sheet is made of polyester/wax formulation.

[0183] It has been determined that the pressure sensitive adhesive isbest applied directly to the adhesive backing material while theadhesive backing material is still at an elevated temperature from theextrusion coating process. A preferred technique is to extrusionlaminate the pressure sensitive adhesive with the adhesive backingmaterial; that is, to apply the pressure sensitive adhesive at nip.Alternately, the adhesive backing material can be reheated before thepressure sensitive adhesive is applied.

[0184] Another preferred embodiment of the present invention, exclusiveof an optional secondary backing material, involves the combination ofthe various process steps described herein together with the use of atleast one substantially linear ethylene polymer with an effective amountof an implosion agent formulated therein in the first layer of a twolayer adhesive backing material. The a preferred combination of processsteps at least includes pre-coating with an aqueous polyolefin system;removal of processing materials by washing or scouring the greige goodwith an aqueous detergent solution heated to at least 67° C.; drying andpre-heating the greige good by subjecting it to infra-red radiation setat about 1000° C. for about 1 to about 6 seconds; extrusion coating theadhesive backing material onto the back surface of the pre-heated,washed primary backing material by utilizing extrusion melt temperaturesof greater than or equal to 615° F. (324° C.); subjecting thesemi-molten or molten adhesive backing material web to a vacuum ofgreater than 40 inches H₂O (9.8 Pa) while at the extrusion coating nip;subjecting the semi-molten or molten adhesive backing material to apositive air pressure device set at greater than about 60 psi (0.41 MPa)at the extrusion coating nip; activating an implosion agent while at theextrusion coating nip; and heat soaking of the carpet by subjecting itto infra-red radiation set at about 1000° C. for about 1 to about 6seconds.

[0185] Various embodiments of the present invention were evaluated and,in specific instances, compared to prior art embodiments. However, theExamples shown should in no way limit the scope of the present inventionto such Examples.

EXAMPLES

[0186] Test Methods

[0187] The primary performance criteria determined for the variousExamples included: tuft bind, abrasion resistance, Velcro rating,flexibility and lamination strength. Tuft bind testing was conducted inaccordance with ASTM D1335-67.

[0188] Moduli for the ethylene polymers used in the present inventionwere measured in accordance with ASTM-790.

[0189] Abrasion resistance was based on a qualitative Velcro fuzzingtest. In this test, a 2 inch (5.1 cm) diameter, 2 pound (0.91 kg) rollercoated with the loop side of standard Velcro was passed 10 times overthe face side of coated carpet samples. The fuzz on the abraded carpetwas then compared to a set of carpet standards and rated on a 1-10 scalewherein a rating of 10 denoted zero fuzzing.

[0190] Flexibility rating was also based on a qualitative assessment.Lamination strength was based on manual qualitative assessment in whicha good delamination rating was given if the various layers of a carpetsample could not be manually pulled apart (i.e., separation of theadhesive backing material from the primary backing material), while apoor rating was given if layers delaminated.

[0191] The Aachen test is used to determine the dimensional stability ofcarpet tile. The Aachen test used herein is ISO Test Method 2551.Briefly described, carpet tiles are first measured in the machine andcross-machine dimensions and then exposed to heat (140° F. (60° C.) for2 hours) and moisture (submerged in water for 2 hours). The carpet tilesare dried for 16 hours in a drying oven. The tiles are then put into aconditioning room for 48 hours, after which each tile is measured in themachine and cross-machine directions. The results are given in terms ofa percent change from the original dimensions.

[0192] Resins

[0193] Table 1 lists the various ethylene polymers used to prepare thevarious Examples. TABLE 1 Melt Index Density Modulus Resin Type (gm/10min) (gm/cc) psi (MPa) A SLEP 30 0.871 2.560 (17.4) B SLEP 30 0.8855.400 (36.7) C SLEP 30 0.900 13.700 (93.2) D SLEP 10 0.900 ND E SLEP 130.871 ND F SLEP 75 0.871 ND G SLEP 75 0.900 ND H SLEP 175 0.900 ND IHBLEP 35 0.882 ND J* LLDPE 5.4 0.921 ND K* LDPE 12 0.916 23.500 (160) L*LDPE 120 0.922 43.000 (293) M* LDPE 150 0.913 ND N* ULDPE 6 0.911 ND O*ULDPE 1 0.912 26.700 (182) P* LLDPE 1 0.920 38.000 (259) Q* HDPE 100.960 182.000 (1238) R* ULDPE 30 0.913 28.400 (193) S* LDPE 55 0.92241.000 (279)

Examples 1-12

[0194] Table 2 summarizes the polymers, extrusion conditions and carpetsample performance results for Inventive Examples 1-8 and ComparativeRuns 9-12. The extrusion coating equipment consisted of a two-extruderBlack Clawson coextrusion line equipped with a 3½ inch (8.9 cm) diameterprimary extruder having a 30:1 L/D and a 2½ inch (6.4 cm) diametersecondary extruder with a 24:1 L/D. For these examples, only the largeextruder was operated at 90 rpms (250 lbs./hr). A 76 cm slot die wasattached to the extruder and was deckled to 69 cm with a 20-mil (0.51mm) die gap and a 6-inch (15.2 cm) air/draw gap. The nip roll pressurewas set at 85 psi (0.58 MPa) and the chill roll was controlled at 60° F.(15.6° C.). The targeted extrusion temperatures, line speed and coatingthicknesses are listed in Table 2.

[0195] Greige good swatches of polypropylene (26 OSY (919.6 cm³/m²),tufted, loop pile, straight stitch greige goods available from ShawIndustries under the designation of Volunteer) were cut and slip sheetedonto Kraft paper for each Example and candidate resins were extrusioncoated onto the backside of the greige goods. Secondary backing material(2.8 OSY (99 cm³/m²)woven polypropylene scrim known as Action Bac®available from Amoco Chemical Company, Fabrics and Fibers Division) wasadded to the backside of greige goods after the disposition of theextrudate at the die and before the nip pressure rollers to form alaminate structure. FIG. 2 shows the extrusion coating method and thesequence of application of an extrusion coated adhesive backing materialfollowed by the application of an optional secondary backing material.In some instances, greige good swatches were first preheated in aconvection oven at 200° F. (93° C.) for 30 min. After coated sampleswere aged for 24 hours at ambient room temperature and 70% relativehumidity, tuft bind, abrasion resistance and delamination weredetermined. TABLE 2 Pre- Melt Line Tuft Temp Thick Coat Wt Temp SpeedBind ° F. mil OSY ° F. ft/min Lamination lbs. Ex. Resin (° C.) (mm)(cm³/m²) (° C.) (m/min) Flex Strength (kg) 1 C Ambient 21 14.5 500 22Good Good 8.0 (0.53) (513) (260) (6.7) (3.6) 2 D Ambient 20 ND 500 22Good Good 7.6 (0.51) (260) (6.7) (3.4) 3 D Ambient  7 ND 500 65 GoodGood 5.0 (0.18) (260) (19.8) (2.3) 4 A 140 ND 15.5 500 22 Good Good 4.6(60) (548) (260) (6.7) (2.1) 5 G 140 ND 13.1 500 22 Good Good 7.0 (60)(463) (260) (6.7) (3.2) 6 F 150 ND 11.9 500 30 Good Good 7.0 (66) (421)(260) (9.1) (3.2) 7 E 160 ND 18.9 500 22 Good Good 10.4 (71) 669) (260)(6.7) (4.7) 8 A 160 ND 11.8 550 30 Good Good 7.6 (71) (417) (288) (9.1)(3.4)  9* R 140 ND 17.6 500 22 Stiff Poor 7.1 (60) (623) (260) (6.7)(3.2) 10* J Ambient 20 ND 500 22 Stiff Poor ND (0.51) (260) (6.7) 11* LAmbient 20 ND 500 22 Stiff Poor ND (0.51) (260) (6.7) 12* S Ambient 20ND 500 22 Stiff Poor ND (0.51) (260) (6.7)

[0196] Inventive Examples 1-8 show that homogeneously branched ethylenepolymers result in carpet samples with good flexibility and goodcohesion of the carpet components and that tuft bind and abrasionresistance are dependent on processing conditions. Two high pressureLDPE, a heterogeneously branched LLDPE, and a heterogeneously branchedULDPE extrusion coating (Comparative Runs 9-12) resulted in relativelystiff carpet samples and relatively poor carpet component cohesiveness.

[0197] One indication of poor component cohesiveness was relatively lowadhesiveness of the backing material to the primary backing material.Another indication was relatively low penetration of the yarn or fiberbundles with the LDPE, LLDPE and ULDPE extrusion coating resins.

Examples 13-22

[0198] Table 3 summarizes the polymers, extrusion conditions, and carpetperformance results for Inventive Examples 13-22. These examples usedthe same extrusion equipment, extrusion conditions and greige goodslisted for Example 1-12. TABLE 3 Pre- Melt Line Tuft Temp Thick TempSpeed Bind ° F. mil ° F. ft/min Lamination lbs. Ex. Resin (° C.) (mm) (°C.) (m/min) Flex Strength (kg) 13 C 175 7 425 65 Good Good 3.6 (79)(0.18) (218) (19.8) (1.6) 14 C 175 7 500 65 Good Good 5.4 (79) (0.18)(260) (19.8) (2.4) 15 C 175 7 550 65 Good Good 6.3 (79) (0.18) (288)(19.8) (2.9) 16 C 175 7 575 65 Good Good 6.6 (79) (0.18) (302) (19.8)(3.0) 17 C 175 7 600 65 Good Good 5.3 (79) (0.18) (316) (19.8) (2.4) 18C 175 15 425 30 Good Good 6.9 (79) (0.38) (218) (9.1) (3.1) 19 C 175 15500 30 Good Good 6.8 (79) (0.38) (260) (9.1) (3.1) 20 C 175 15 550 30Good Good 8.3 (79) (0.38) (288) (9.1) (3.8) 21 C 175 15 575 30 Good Good6.2 (79) (0.38) (302) (9.1) (2.8) 22 C 175 15 600 30 Good Good 6.2 (79)(0.38) (316) (2.8)

[0199] Inventive Examples 13-22 show the effect of coating thickness andextrusion temperature on carpet backing performance. In certain aspectsof the present invention, coating thicknesses greater than 7 mils (0.18mm), preferably greater than or equal to 11 mils (0.38 mm), morepreferably greater than or equal to about 15, and most preferablygreater than or equal to 22 mils (0.56 mm) are preferred for extrusionmelt temperatures greater than 550° F. (288° C.), preferably greaterthan or equal to 575° F. (302° C.), more preferably greater than orequal to 600° F. (316° C.) and most preferably greater than or equal to615° F. (324° C.). Practitioners will appreciate that extrusion melttemperature and extrusion line speed are inversely related. That is,lower extrusion temperatures will generally require slower extrusionline speeds to achieve good penetration of the yarn. Practitioners willalso appreciate that at elevated temperatures, thermal stabilizationadditives such as Irganox® 1010 and Irgafos® 168 (both supplied byCiba-Geigy) may be required to achieve the full benefit of the presentinvention such as, for example, adhesive backing material penetration ofthe yarn or fiber bundles greater than 40 percent. Practitioners willalso appreciate that excessive chemical stabilization may adverselyeffect draw down performance, thus additive selection and concentrationmust be balanced against draw down requirements and penetrationrequirements. However, in general, higher additive concentrations willbe required at higher extrusion melt temperatures.

Examples 23-54

[0200] Table 4 summarizes the polymers, extrusion conditions and carpetperformance results for Examples 23-54. In this evaluation, theextrusion coating equipment consisted of a 3½ inch (8.9 cm) diameterBlack Clawson Model 435 extruder equipped with a 30:1 L/D screw, a 150hp (311 Joules/hr) Electro Flight drive system, a Cloreren 3-layerfeedblock, and a Black Clawson Model 300 XLHL 30″ coat hanger dieexternally deckled to 24 inches (61 cm) using a 20 mil (0.51 mm) die gapand a 6 inch (15.2 cm) air/draw gap. The targeted extrusiontemperatures, screw speed, line speed and coating thicknesses are listedin Table 4.

[0201] Samples of polypropylene greige goods (26 OSY (920 cm³/m²),tufted, loop pile, straight stitch greige goods supplied by ShawIndustries under the designation of Volunteer) were used. Candidateethylene polymers were extrusion coated onto the backside of greigegoods that were run continuously through the extrusion coater ratherthan slip sheeted as individual greige good swatches. Electric andgas-fired infrared heaters were installed prior to the coating stationto preheat the greige goods. A partitioned vacuum pressure roll with a45° vacuum section was installed and attached to a variable vacuum pump.The vacuum section was positioned at the contact point of extrudate andgreige goods. The nip roll pressure was set at 80 psi and the chill rollwas controlled at 120° F. (49° C.). Secondary backing material (2.8 OSY99 cm³/m²) woven polypropylene scrim or Action Bac® available from AmocoChemical Company, Fabrics and Fibers Division) was added to the backsideof the carpet samples after disposition of the extrudate at the die andbefore the nip pressure rollers to form a laminate structure. Aftercoated samples were aged for 24 hours at ambient and 70% relativehumidity, tuft bind, abrasion resistance and delamination resistancewere determined. TABLE 4 Melt Line Pre-Temp Coat Weight Temp Screw SpeedVac Tuft Bind ° F. Thick OSY ° F. Speed ft/min in H₂O Lamination lbs.Ex. Resin (° C.) mil (cm³/m²) (° C.) rpm (m/min) (Pa) Flex Strength (kg)23 C Ambient ND 11.6 500 20 18  0 Good Good  8.6 (410) (260) (5.5) (3.9)24 C Ambient ND 14.2 500 25 18  0 Good Good  7.9 (502) (260) (5.5) (3.6)25 C Ambient ND 17.8 500 30 18  0 Good Good 10.1 (630) (260) (5.5) (4.6)26 B Ambient ND  9.7 500 20 18  0 Good Good  9.0 (343) (260) (5.5) (4.1)27 B Ambient ND 13.0 500 25 18  0 Good Good  7.0 (460) (260) (5.5) (3.2)28 B Ambient ND 14.2 500 30 18  0 Good Good  9.1 (502) (260) (5.5) (4.1)29 G 200 ND  6.9 400 ND 18  0 Good Good  6.6 (93) (244) (204) (5.5)(3.0) 30 G 200 ND 11.8 400 ND 18  0 Good Good  8.4 (93) (417) (204)(5.5) (3.8) 31 H 200 ND 10.2 400 ND 18  0 Good Good  7.3 (93) (361)(204) (5.5) (3.3) 32 B 150 ND  8.0 500 24 26 20 Good Good ND (66) (283)(260) (7.9) (4.9) 33 B 150 ND  7.7 500 24 26 10 Good Good ND (66) (272)(260) (7.9) (2.5) 34 B 150 ND  7.8 500 24 26  0 Good Good ND (66) (276)(260) (7.9) 35 B 150 ND  3.9 500 48 26  0 Good Good ND (66) (138) (260)(7.9) 36 B 150 ND 15.8 500 48 26 10 Good Good  8.7 (66) (559) (260)(7.9) (2.5) (3.9) 37 B 150 ND 15.4 500 48 26 25 Good Good  9.6 (66)(545) (260) (7.9) (6.1) (4.4) 38 B 150 ND 14.8 550 48 26 25 Good Good 7.6 (66) (523) (288) (7.9) (6.1) (3.4) 39 B 150 ND 18.0 550 48 26 20Good Good  8.2 (66) (637) (288) (7.9) (4.9) (3.7) 40 G 175 ND 10.7 40026 26 25 Good Good ND (79) (378) (204) (7.9) (6.1) 41 G 175 ND  9.2 40026 26 10 Good Good ND (79) (325) (204) (7.9) (2.5) 42 G 175 ND  9.5 40026 26  2.5 Good Good ND (79) (336) (204) (7.9) (0.6) 43 G 175 ND 27.2400 55 26  2.5 Good Good 10.9 (79) (962) (204) (7.9) (0.6) (4.9) 44 G175 ND 26.0 400 55 26 10 Good Good  8.8 (79) (920) (204) (7.9) (2.5)(4.0) 45 G 175 ND 17.8 400 55 26 25 Good Good 10.2 (79) (630) (204)(7.9) (6.1) (4.6) 46 C 250 ND  9.8 500 24 26 25 Good Good 10.9 (121)(347) (260) (7.9) (6.1) (4.9) 47 C 250 ND  9.6 500 24 26 10 Good Good 9.9 (121) (340) (260) (7.9) (2.5) (4.5) 48 C 250 ND  9.3 500 24 26  2.5Good Good ND (121) (329) (260) (7.9) (0.6) 49 C 250 ND 16.6 500 51 26 2.5 Good Good  6.8 (121) (587) (260) (7.9) (0.6) (3.1) 50 C 250 ND 17.5500 51 26 10 Good Good  7.0 (121) (619) (260) (7.9) (2.5) (3.2) 51 C 250ND 16.6 500 51 26 25 Good Good  7.6 (121) (587) (260) (7.9) (6.1) (3.4)52 C 245 ND 10.2 500 50 26 50 Good Good  7.8 (118) (361) (260) (7.9)(12.3) (3.5) 53 C 245 ND 19.8 500 50 26 50 Good Good 10.8 (118) (700)(260) (7.9) (12.3) (4.9)  54* L 200 15 ND 400 ND 18  0 Stiff Poor ND(93) (0.38) (204) (5.5)

[0202] These Examples show that homogeneously branched ethylene polymersresult in carpet samples with good flexibility and good cohesion ofcarpet components, and that tuft bind strength and abrasion resistanceare dependent on processing conditions. These Examples also show theimprovement in carpet backing performance is attainable by theutilization of a carpet preheating process step, optimized coatingthickness, and/or a vacuum nip pressure process step.

[0203] The high pressure LDPE extrusion coating resin resulted in stiffcarpet with poor component cohesiveness.

Examples 55-77

[0204] Table 5 summarizes the polymers, extrusion conditions and carpetperformance results for Examples 55-77. These examples employed the sameextrusion equipment and extrusion conditions listed for Examples 23-54,with the exception that nylon greige goods (26 OSY (920 cm³/m²), tufted,loop pile, straight stitch greige goods available from Shaw Industriesunder the designation of Vocation™) were used instead of polypropylenegreige goods. TABLE 5 Coat Line Pre-Temp Weight Melt Temp Screw SpeedVacuum ° F. OSY ° F. Speed ft/min in H₂O Lamination Ex. Resin (° C.)(cm³/m²) (° C.) RPM (m/min) (Pa) Flex Strength 55 C Ambient 18.4 500 2518  0 Good Good (651) (5.5) 56 C Ambient 18.9 500 30 18  0 Good Good(668) (5.5) 57 C Ambient 20.2 500 35 18  0 Good Good (714) (5.5) 58 BAmbient 12.1 500 25 18  0 Good Good (428) (5.5) 59 B Ambient 17.2 500 3018  0 Good Good (608) (5.5) 60 B Ambient 18.1 500 35 18  0 Good Good(640) (5.5) 61 G 200  8.4 400 ND 18  0 Good Good (93) (297) (5.5) 62* L200 13.6 400 ND 18  0 Poor Poor (93) (481) (5.5) 63 B 150 17.6 550 48 2622 Good Good (66) (623) (7.9) (5.4) 64 B 150 15.1 550 48 26 11 Good Good(66) (534) (7.9) (2.7) 65 B 150 16.4 550 48 26  2.5 Good Good (66) (580)(7.9) (0.6) 66 G 175 16.9 400 26 26 25 Good Good (79) (598) (7.9) (6.1)67 G 175 16.6 400 26 26 10 Good Good (79) (587) (7.9) (2.5) 68 G 17517.3 400 26 26  2.5 Good Good (79) (612) (7.9) (0.6) 69 G 175  8.0 40055 26  2.5 Good Good (79) (283) (7.9) (0.6) 70 G 175  8.4 400 55 26 10Good Good (79) (297) (7.9) (2.5) 71 G 175  8.3 400 55 26 25 Good Good(79) (294) (7.9) (6.1) 72 C 260 18.8 500 24 26 25 Good Good (127) (665)(7.9) (6.1) 73 C 260 16.6 500 24 26 10 Good Good (127) (587) (7.9) (2.5)74 C 260 16.6 500 24 26  2.5 Good Good (127) (587) (7.9) (0.6) 75 C 260 8.1 500 51 26  2.5 Good Good (127) (286) (7.9) (0.6) 76 C 260  8.1 50051 26 10 Good Good (127) (286) (7.9) (2.5) 77 C 260  7.9 500 51 26 25Good Good (127) (279) (7.9) (6.1)

[0205] Inventive Examples 55-77 show also that homogeneously branchedethylene polymers result in carpet samples with good flexibility andgood cohesion of the carpet components, and that tuft bind strength andabrasion resistance are dependent on processing conditions. LikeExamples 23-53, these examples also show that improvements in carpetbacking performance are attainable by employing a preheat process step,optimum coating thickness and/or a vacuum nip pressure process step.

Examples 78-86

[0206] Table 6 summarizes the polymers, extrusion conditions and carpetperformance results for Examples 78-86. These examples used the sameextrusion equipment and extrusion conditions listed for Examples 1-12,with the exceptions that cross stitch polypropylene greige goods (20 OSY(707 cm³/m²), tufted, loop pile available from Shaw Industries under thestyle name of “Proton”) were used instead of straight stitch goods TABLE6 Pre- Coat Melt Line Tuft Temp Weight Temp Speed Bind ° F. OSY ° F.ft/min Lamination lbs. Abrasion Velcro Ex. Resin (° C.) (cm³/m²) (° C.)(m/min) Flex Strength (kg) Resistance Test 78 C Ambient  7.7 500 48 GoodGood  8.5 Good 8 (272) (260) (14.6) (3.9) 79 C 175 16.9 500 22 Good Good14.3 Good 9 (79) (598) (260) (6.7) (6.5) 80 E 175  9.9 500 48 Good Good10.2 Good 9 (79) (350) (260) (14.6) (4.6) 81 E 175 17.3 500 22 Good Good13.2 Good 9 (79) (612) (260) (6.7) (6.0) 82 D 175 17.8 500 22 Good Good12.9 Good 9 (79) (630) (260) (6.7) (5.9) 83 D 175  9.2 500 48 Good Good 7.6 Good 9 (79) (325) (260) (14.6) (3.4)  84* J 175  9.7 500 48 StiffPoor  8.7 Good 9 (79) (343) (260) (14.6) (3.9)  85* J 175 16.3 500 22Stiff Poor 10.4 Good 9 (79) (577) (260) (6.7) (4.7)  86* J Ambient 18.6500 22 Stiff Poor  9.1 Good 9 (658) (260) (6.7) (4.1)

[0207] Inventive Examples 78-83 show that homogeneously branchedethylene polymers result in cross-stitched carpet samples with goodflexibility and good cohesion of the carpet components. The LLDPEextrusion coating resin used for Comparative Runs 84-86 resulted instiff cross-stitched carpet samples.

Examples 87-90

[0208] Table 7 summarizes the polymers, extrusion conditions and carpetperformance results for Inventive Examples 87-90. These examples usedthe same extrusion equipment and extrusion conditions as listed forExamples 23-54, with the exceptions that polypropylene greige goods,namely a 2750 denier polypropylene yarn tufted at 16 OSY (566 cm³/m²) ina loop pile, straight stitch, and available from Shaw Industries underthe style name “Quadratic,” were used instead of polypropylene greigegoods. In addition, for Examples 88-90, the greige goods were coatedwith an olefinic suspension or emulsion, known as a pre-coat, prior toextrusion coating.

[0209] In particular, an aqueous dispersion of polyethylene particleswas prepared by weighing out 200 parts water. Next, 0.4 parts of asurfactant from Ciba-Geigy under the designation “Igepal CO-430” wasdispersed in the water using a high speed homogenizer at low speed.Then, 100 parts “FN500” from Quantum Chemical was added to the mixtureusing medium to high mixing speeds for approximately 5 minutes. Afterthe FN500 began agitating, 0.4 parts of a defoamer from Lenmar under thedesignation “Marfoam” were added to reduce the foaming of the mixture.Finally, 2.4 parts of a thickener sold by Sun Chemical Internationalunder the designation “Printgum 600M” was added to the mixture. Aminimum of 10 minutes of mixing was needed after adding this thickener.

[0210] This dispersion was applied to the back of the primary backing byconventional means. In particular, 38 OSY (1,344 cm³/m²), based on thewet dispersion, were applied to the non-pile side of the primary backingby a roll over roller applicator running at 10 feet per minute (3.05m/min).

[0211] After the dispersion was applied, the carpet passed directly intoa conventional high velocity drying oven. The total dwell time in theoven was 5 minutes and the carpet reached a final temperature of about290° F. (143° C.).

[0212] Observations made before after the pre-coat was applied, butbefore application of an extruded adhesive backing material showed thatthe carpet thus produced had good bundle penetration and wrap.Measurements showed that 4 and 8 OSY (283 cm³/m²)of the FN500, based ondry weight, were added to the carpet backing.

[0213] Before application of an extruded adhesive backing, the carpet ofExamples 88-90 was also tested according to test method ASTM D1335 tomeasure the tuft bind strength of the carpet (See, 1991 Annual Book ofASTM Standards, Volume 07.01). This test measures the force required topull one or both legs of a loop in a loop pile carpet free from thebacking. The carpet made in Example 88-90 showed an average tuft bindstrength of 9.0 pounds (4.1 kg) before application of the extrudedadhesive backing.

[0214] Example 87 included a pre-coat of Adcote™50T4990, an ethyleneacrylic acid copolymer dispersion available from Morton International,Woodstock, Ill. applied at 4 OSY (141.5 cm³/m²).

[0215] No vacuum was applied for these Examples. TABLE 7 Pre- Coat MeltTuft Temp Pre-Coat Weight Temp bind ° F. Type/ OSY ° F. Lamination lbs.Abrasion Velcro Ex. Resin (° C.) OSY (cm³/m² (° C.) Flex Strength (kg)Resistance Test 23 C Ambient None 11.6 500 Good Good  8.6 Poor 2 (410)(260) (3.9) 87 C Ambient Adcote/4  3.9 500 Good Good 10.7 Good 8 (138)(260) (4.9) 88 C 175 LDPE/8  8.8 500 Good Good  8.2 Good 9 (79) (311)(260) (3.7) 89 E 175 LDPE/4 ND 500 Good Good 10.0 Good 8 (79) (260)(4.5) 90 E 175 LDPE/8  5.5 500 Good Good 11.3 Good 9 (79) (195) (260)(5.1)

[0216] Inventive Examples 87-90 show that homogeneously branchedethylene polymers result in carpet samples with good flexibility andgood cohesion of the carpet components, and that carpet performance canbe enhanced by the application of a pre-coat.

Examples 91-96

[0217] Table 8 summarizes the polymers, extrusion conditions, andresults for Examples 91-96. These Examples used the same extrusionequipment and extrusion conditions as listed for Examples 23-54, withthe exceptions that nylon greige goods, namely a 3050 denier nylon 6,tufted at 20 OSY (707 cm³/m²), in a loop pile, straight stitch andavailable from Shaw Industries under the style name “Vanguard™,” wereused instead of straight stitch goods and the greige goods were coatedwith an olefinic suspension or emulsion (i.e., a pre-coat) prior to theextrusion coating step. No vacuum was applied for these Examples. Thepre-coats evaluated included Adcote™50T4990, an ethylene acrylic acidcopolymer dispersion available from Morton International, Woodstock,Ill. and a LDPE suspension wherein for the latter the pre-coated greigegoods was available from Shaw Industries under the designation ofVanguard™. These pre-coats were applied at 4 (141.5 cm³/m²)and 8 OSY(283 cm³/m²)weights. TABLE 8 Pre- Coat Melt Tuft Temp Pre-Coat WeightTemp Bind ° F. OSY OSY ° F. Lamination lbs. Abrasion Velcro Ex. Resin (°C.) (cm³/m²) (cm³/m²) (° C.) Flex Strength (kg) Resistance Test 91 G 150Adcote/4  8.7 500 Good Good 10.7 Good 9 (66) (308) (260) (4.9) 92 G 150LDPE/8 10.0 500 Good Good  7.0 Fair 5 (66) (354) (260) (3.2) 93 G 150LDPE/8  9.3 500 Good Good  5.0 Fair 6 (66) (329) (260) (2.3) 94 G 150Adcote/4  6.3 500 Good Good 12.1 Good 8 (66) (223) (260) (5.5) 95 G 150LDPE/8  6.1 500 Good Good  6.3 Good 7 (66) (216) (260) (2.9) 96 G 150LDPE/4  3.2 500 Good Good  9.2 Good 9 (66) (113) (260) (4.2)

[0218] These examples show that homogeneously branched ethylene polymersresultin carpet samples with good flexibility and good cohesion of thecarpet components, and that carpet performance can be enhanced by theapplication of an aqueous pre-coat.

Examples 97-109

[0219] Table 9 summarizes the polymers, extrusion conditions and carpetperformance results for Inventive Examples 97-109. These Examples usedthe same extrusion equipment, extrusion conditions and greige goodslisted for Examples 1-12, with the exception that a dual lip or twostation extrusion coating technique was evaluated. In this evaluation,greige goods were first extrusion coated with a layer next to thebackside of the carpet. This layer was identified as the bottom layer.Once coated, samples were then extrusion coated again with layer,identified as the top layer. TABLE 9 Melt Thick Thick Temp Line Tuft TopBottom Top Speed bind Top Bottom mil mil ° F. ft/min Lamination lbs. Ex.Resin Resin (mm) (mm) (° C.) (m/min) Flex Strength (kg) 97 C A 15 5 57560 Good Good 5.2 (0.38) (0.13) (302) (2.4) 98 C C 15 5 575 60 Good Good4.5 (0.38) (0.13) (302) (2.0) 99 C G 15 5 575 60 Good Good 5.5 (0.38)(0.13) (302) (2.5) 100 C F 15 5 575 60 Good Good 5.0 (0.38) (0.13) (302)(2.3) 101 D A 15 5 625 60 Good Good 7.1 (0.38) (0.13) (329) (3.2) 102 DC 15 5 625 60 Good Good 4.9 (0.38) (0.13) (2.2) 103 D G 15 5 625 60 GoodGood 6.2 (0.38) (0.13) (329) (2.8) 104 D F 15 5 625 60 Good Good 7.5(0.38) (0.13) (329) (3.4) 105 C A 15 5 625 60 Good Good 8.4 (0.38)(0.13) (329) (3.8) 106 C C 15 5 625 60 Good Good 5.7 (0.38) (0.13) (329)(2.6) 107 D A 15 5 625 60 Good Good ND (0.38) (0.13) (329) 108 D C 15 5625 60 Good Good 7.0 (0.38) (0.13) (329) (3.2) 109 C F 15 5 600 90 GoodGood 6.8 (0.38) (0.13) (316) (3.1)

[0220] Inventive Examples 97-109 show that two station extrusion ofhomogenously branched ethylene polymers results in carpet samples withgood flexibility and good cohesion of the carpet components. The toplayer can also contain fillers or recycled polymeric materials to modifyproperties or for cost savings.

Examples 110-117

[0221] Table 10 summarizes the polymers, extrusion conditions and carpetperformance results for Inventive Examples 110-117. These Examples usedthe extrusion equipment, greige goods and extrusion conditions as listedfor Examples 1-12, with the exception that a single die coextrusiontechnique was used. Different candidate ethylene polymers wereintroduced into both extruders, respectively. The ethylene polymers werethen fed simultaneously into a single die and coextruded onto thebackside of the greige goods. The layer extruded onto the backside ofthe carpet (i.e., adjacent to the primary backing material) wasidentified as the bottom layer, while the outer layer was identified asthe top layer. Different thicknesses were evaluated and different melttemperatures were used. TABLE 10 Melt Melt Thick Thick Temp Temp LineTuft Top Bottom Top Bottom Speed Bind Top Bottom mil mil ° F. ° F.ft/min Lamination lbs. Ex. Resin Resin (mm) (mm) (° C.) (° C.) (m/min)Flex Strength (kg) 110 C A 15 5 525 475 22 Good Good 8.2 (0.38) (0.13)(274) (246) (6.7) (3.7) 111 C G 15 5 525 475 22 Good Good 7.8 (0.38)(0.13) (274) (246) (6.7) (3.5) 112 C F 15 5 525 475 22 Good Good 8.1(0.38) (0.13) (274) (246) (6.7) (3.7) 113 D F 15 5 525 475 22 Good Good5.6 (0.38) (0.13) (274) (246) (6.7) (2.5) 114 C A 10 5 525 475 30 GoodGood 7.9 (0.25) (0.13) (274) (246) (9.1) (3.6) 115 C G 10 5 525 475 30Good Good 5.9 (0.25) (0.13) (274) (246) (9.1) (2.7) 116 C F 10 5 525 47530 Good Good 8.1 (0.25) (0.13) (274) (246) (9.1) (3.7) 117 C F 15 5 550500 22 Good Good 7.5 (0.38) (0.13) (288) (260) (6.7) (3.4)

[0222] Inventive Examples 110-117 show that single die coextrusion ofhomogeneously branched ethylene polymers results in carpet samples withgood flexibility and good cohesion of the carpet components. The toplayer can also contain fillers or recycled polymeric material to modifyproperties or provide for cost savings.

Examples 118-122

[0223] As a simulation of extrusion coating, a compression moldingmethod was developed to melt plaques of candidate resins on to thebackside of greige goods. This method employs a programmable press. Thefollowing lists the procedure.

[0224] Ethylene polymer pellets granules or powder were pressed intoplaques weighing approximately 16 grams and having a thickness of 0.025inches (0.64 mm). The press used was a pneumatic Tetrahedronprogrammable press. The polymer pellets, granules or powder were placedbetween Mylar brand polyester film in the desired plaque mold andpreheated for 30 seconds at 374° F. (190° C.) (this was accomplished byinserting the samples into the pre-heated press and closing the platenssufficiently to allow for heating of the polymer sample withoutcompressing it). After 30 seconds, the platens were completely closedand the Tetrahedron program was started. The program provided 2 tons(1,814 kg) compression at 374° F. (190° C.) for 1.5 minute and 50 tons(4.5×10⁴ kg) compression at 100° F. (38° C.) cooling for 5 minutes. Oncethe program had ended, the sample was removed and further cooled.Samples were then stored for later use in a compression lamination stepwith greige good squares.

[0225] Greige goods were cut into squares (slightly larger than the sizeused to mold the ethylene polymer samples as described above) and tapedonto an insulation board. The sample squares were then preheated for 15minutes in a Hot Pack oven set at 110° C.

[0226] Ethylene polymer plaques as prepared above were placed on Mylarbrand polyester film and set into the preheated press (374° F.) (190°C.) for 5 minutes. The press platens were closed sufficiently topre-heat the plaques without compressing them. The greige good squares,which had been preheated for about 5 minutes at about 374° F. (190° C.),were then taken from the Hot Pack oven and introduced to the press(i.e., inverted onto preheated polymer plaques. At the instant thepolymer plaques and greige good squares were married, approximately 0.1ton (90.7 kg) of force was applied and then the press was immediatelyopened. The laminated samples were then taken out of the press andallowed to cool to ambient room temperature. The amount of time requiredto compression laminate the greige good squares and the polymer plaqueswas about 3-7 seconds.

[0227] Table 12 gives molding conditions and performance results forvarious homogeneously branched substantially linear ethylene polymers.TABLE 12 Tuft bind lbs. Example Resin (kg) 118 C 17.7 (8.0) 119 B 14.3(6.5) 120 A 11.2 (5.1) 121 G 17.5 (7.9) 122 H 12.8 (5.8)

Examples 123-131

[0228] To measure the adhesion of candidate ethylene polymers to greigegood squares, the compression lamination method described for Examples118-122 was used. Peel strengths were then measured using an Instron setat a 25 mm/minute cross-head speed.

[0229] Table 13 gives adhesion results for various homogeneouslybranched ethylene polymers, high pressure LDPE, heterogeneously branchedULDPE, heterogeneously branched LLDPE, and HDPE laminated to squaresmade from polypropylene carpet greige goods. TABLE 13 Adhesion Strength,lbs. Example Resin (kg) 123 E 7.83 (3.6) 124 B 4.82 (2.2) 125 C 1.77(0.8) 126 G 3.19 (1.4) 127 I 4.73 (2.1)  128* P 0.40 (0.2)  129* N 1.60(0.7)  130* O 1.41 (0.6)  131* M 1.79 (0.8)  132* Q 0.49 (0.2)

[0230] These Examples show that homogeneously branched substantiallylinear ethylene polymers and homogeneously branched linear ethylenepolymers provide superior adhesion relative to ordinary polyolefinresins and as such result in enhanced performance when used as adhesivebacking materials.

[0231] The interface of carpet sample cross-section were captured inphotomicrographs using a scanning electron microscope to assess theadhesive interaction between various carpet components. FIG. 3 is aphotomicrograph of the interface cross-section of Example 18 at 20× and50× magnifications. FIG. 4 is a photomicrograph of the interfacecross-section of Example 22 at 20× and 50× magnifications. WhereasExample 18 was found to possess only fair carpet performance, Example 22was found to possess relatively good carpet performance. The improvedperformance of Example 22 is attributed to the enhanced intimate contactbetween the adhesive backing material and the primary backing materialand to the substantial encapsulation of fiber bundles due to enhancedbundle penetration. The enhanced bundle penetration of Example 22relative to Example 18 is clearly evident when comparing FIG. 3 and FIG.4.

[0232] To quantify bundle penetration, digital image analysis wasperformed using a Quantimet 570 imager available from Leica, Inc.Deerfield, Ill. and running Version 2.0 QUIC software. Digital imageswere obtained from a scanning electron microscope through a Sanyo VDC3860 CCD video camera equipped with a Javelin 12.5-75 mm zoom lens.

[0233] The total cross-section area of a fiber bundle was defined bytracing over the digital image using the binary edit feature of the QUICsoftware. The void cross-section area (i.e., area of no backing materialpenetration) of the bundle was determined in the same manner as for thetotal cross-section area. Bundle penetration was then calculated as oneminus the ratio of void to bundle areas.

[0234]FIG. 5 shows the relationship of between bundle penetration andtuft bind strength for nylon and polypropylene carpets. Extrusion coatedethylene polymer bundle penetrations greater than 40 percent, preferablygreater than or equal to 60 percent, more preferably greater than orequal to 80 percent and most preferably greater than or equal to 90percent are required for good carpet performance.

[0235] Also, FIG. 5 indicates that lower fiber bundle penetration levelsare required for nylon carpet to achieve the same level of abrasionresistance as for polypropylene carpet. Here, the nylon carpet has twoimportant differences relative to the polypropylene carpet. For one, thenylon carpet was washed with a mild aqueous detergent solution as partof the dyeing operation. Secondly, the nylon carpet fibers are polarwhile the polypropylene carpet fibers are nonpolar. However, the resultin FIG. 5 of a lower fiber bundle penetration requirement for the nyloncarpet is unexpected and surprising in that although a nonpolar adhesivebacking material is employed, high abrasion performance appears to beobtained easier with a washed or scoured polar carpet (i.e., nylon)relative to the nonpolar carpet (i.e., polypropylene). Ordinarily, oneskilled in the art would expect like materials to better attract oneanother and thereby require less penetration of the adhesive backingmaterial into the fiber bundles for a given level of abrasionresistance. This result is also surprising in that homogeneouslybranched ethylene polymers have been shown in U.S. Pat. No. 5,395,471 toexhibit improved adhesion to polypropylene substrates yet here betterresults are obtained for nylon fibers over polypropylene fibers. Theseresults indicated that selection of the adhesive backing material formechanical bonding and a scouring or washing process step can compensatefor the lack of or reduced chemical interactions between the variouscarpet components.

Examples 133-141

[0236] To indicate the relative ability of candidate ethylene polymersto penetrate carpet yarn or fiber bundles at reasonable processingtemperatures and thereby provide good carpet performance, solidificationtemperature testing was performed. In this test, candidate ethylenepolymers were tested in the Temperature Sweep mode on a RheometricsMechanical Spectrometer 800E (S/N 035-014) fitted with a cone/cylinderfixture. The dimensions of the fixture were 52 mm (cup insidediameter)×50 mm (bob outside diameter)×17 mm (bob height)×0.04 (coneangle). The gap between the bob and cup was calibrated to 50 μm±2 μm atroom temperature and zero gap at 220° C. Samples were loaded into thecup and heated until molten. The gap was set to 50 μm±2 μm as soon asthe bob was pushed in. Any excess amount of samples or overflow wascleaned away. The solidification measurement was initiated when the tooltemperature reached 220° C. The cup was oscillated at 1 Hz and 20%dynamic strain. The experiment proceeded by a first slow cool rate from220° C. to 110° C. at a 10° C./step. Samples were treated to a secondslow cool rate of 5° C./step from 110° C. to 40°C. To prevent anycontraction of the fixture, auto-tension was applied to keep the normalforce slightly above zero. The auto-tension was set as: 5gram(pre-tension), 1 gram sensitivity and 100 dyne/cm² (1.02 kg/m²) lowlimit. When samples solidified, high torque was suddenly generated. Anauto-strain was applied to prevent transducer from overloading beforethe sample was completely solidified. The auto-strain was set as: 100%maximum applied strain, 100 g-cm maximum allowed torque, 10 g-cm minimumallowed torque and 50% strain adjustment. The entire experiment wasconducted in a dried nitrogen environment to minimize sampledegradation.

[0237] Table 14 gives solidification temperatures for homogeneouslybranched ethylene polymers and a high pressure LDPE extrusion coatingresin. TABLE 14 Example Run Solidification Temp, ° C. 133 B 83 134 C 91135 G 94 136 E 76 137 H 95 138 A 70 139 F 71 140 I 77  141* S 106 

[0238] These Examples show that homogeneously branched ethylene polymershave relative low solidification temperatures and, as such, a betterability to penetrate carpet yarns or fiber bundle compared to ordinarylow density polyethylenes. Olefin polymers suitable for use in thepresent invention are thought to have solidification temperatures lessthan 100° C., preferably less than or equal to 90° C., more preferablyless than or equal to 85° C., and most preferably less than or equal to80° C. In certain embodiments of the present invention, thesolidification temperature of the olefin extrusion coating resin,wherein homogeneously branched ethylene-polymers are preferred, is inthe range of from about 65 to about 100° C., preferably from about 70 toabout 90° C. and more preferably from about 70 to about 85° C.

Examples 142-152

[0239] In another evaluation, a wet vacuum scouring and washingtechnique was investigated to determine its effect on the performance ofadhesive backing materials of the present invention.

[0240] The evaluation consisted of two different wet vacuumingprocedures. The first wet vacuuming procedure (denoted Vac #1 in thetable below) consisted of cleaning the backside of greige good samples(i.e., the primary backing material side as opposed to the fiber faceside) using a commercial wet vacuum carpet cleaner equipped with adispensing/fill tank, Rinsenvac™ Carpet Cleaning System supplied by BlueLustre Products, Inc., Indianapolis, Ind., filled to dispense ambienttemperature tap water as the cleaning solution. When the first wetvacuuming procedure was used, the greige good samples were subjected totwo separate wet vacuum cleanings and were completely air dried aftereach cleaning. The second wet vacuuming procedure (denoted Vac #2 in thetable below) consisted of cleaning the backside of greige good samplesusing the Rinsenvac™ Carpet Cleaning System filled to dispense a hot(90° C.) aqueous solution of dilute Rinsenvac™ Professional CarpetCleaner as the cleaning solution mixture. The concentration of thecleaning solution for the second wet vacuuming procedure was 10 partstap water to 1 part Rinsenvac™ detergent. When the second wet vacuumingprocedure was used, the greige good samples were subjected to one wetvacuum cleaning followed by complete air drying, a rinse using ambienttemperature water and then a final complete air drying step. For eachwashing procedure, 0.5 gallons (1.9 liters of cleaning solution wasdispensed per 5 yd²(4.2 m²) of greige goods.

[0241] In this evaluation, unwashed (control samples) and washed tuftedgreige good samples were extrusion coated using a monolayer dieconfiguration, although a single die coextrusion and dual lipcoextrusion can also be used. Auxiliary equipment included: pre-heatersand heat soak ovens.

[0242] The extrusion coating equipment consisted of a two-extruder BlackClawson coextrusion line with a 3½ inch (8.9 cm) diameter primaryextruder with a 30:1 L/D and a 2½ inch (6.4 cm) diameter secondaryextruder with a 24:1 L/D. For these examples, only the large extruderwas operated at variable rates. A 76 cm slot die is attached and deckledto 69 cm with a 20 mil (0.51 mm) die gap and a 6 inch (15.2 cm) air/drawgap. The nip roll pressure was set at 30 psi (0.2 MPa) and the chillroll temperature was varied.

[0243] The greige good were swatches of Volunteer™ carpet supplied byShaw Industries. Volunteer carpet consists of polypropylene fibers at 26oz/yd² (920 cm³/m²)and is characterized as a tufted, loop pile, singlestitch carpet. Both control unwashed and washed greige good samples wereslip sheeted onto Kraft paper during extrusion coating to apply theadhesive backing material. Both unwashed control samples and washedsamples were first preheated in a convection oven prior to applying theextrusion coated adhesive backing material.

[0244] A substantially linear ethylene polymer, designated XU-59100.00as supplied by The Dow Chemical Company, was used as the adhesivebacking material in this evaluation. XU-59100.00 is characterized ashaving a 30 g/10 min. melt index and a 0.900 g/cc polymer density. Thepre-heat measured temperature was set at 160° F. (71° C.), extrusioncoating melt temperature was set at 500° F. (260° C.), the chill rolltemperature was set at 80° F. (27° C.) and the extrusion coating linespeed was set at 85 ft/min (26 m/min).

[0245] After the extrusion coated samples were allowed to age for atleast 24 hours at ambient room temperature, tuft bind, abrasionresistance and delamination performance were measured. Tuft bind testingwas conducted according to ASTM D-1335-67. Abrasion resistance resultswere obtained using a Velcro test procedure wherein a 2 inch (51 mm)diameter, 2 pound (0.91 kg) roller coated with the loop side of standardVelcro was passed 10 times over the face side of coated carpet samples.The fuzz on the abraded carpet was then compared to a set of carpetstandards and rated on a 1-10 scale (10 denoting zero fuzz). Abrasionresistance was also quantified using the Fiber Lock Test which isdescribed hereinbelow. In general, if the Velcro Number was below 6 orthe abrasion resistance of the carpet sample was rated poor, tuft bindswere not measured. The following Table 15 summarizes the results of thisevaluation. TABLE 15 Resin Tuft Coating Bind Velcro Fiber Wet Wt. -oz/yd² lbs. Rating Lock Example Vacuuming (cm³/m²) (kg) Number. Fuzz No.142 None  5.0 ND 0.5 385 (177) 143 None  7.2 ND 4.3 220 (255) 144 None11.3 7.4 7.5 78 (400) (3.4) 145 None 10.4 8.5 7.4 81 (368) (3.9) 146 Vac#1  5.5 7.4 8 60 (195) (3.4) 147 Vac #1  8.0 7.4 8 61 (283) (3.4) 148Vac #1 10.6 7.7 9 25 (375) (3.5) 149 Vac #1 11.0 6.7 8 40 (389) (3.0)150 Vac #2  7.1 8.3 8 76 (251) (3.8) 151 Vac #2  7.9 8.8 8 52 (279)(4.0) 152 Vac #2 10.2 8.4 8 42 (361) (3.8)

[0246] The results in Table 15 show that, at equivalent adhesive backingmaterial coating weights, the use of a wet vacuuming process step priorto the application of the adhesive backing material can significantlyimprove carpet performance relative to unwashed samples. The improvementis so dramatic that substantially reduced adhesive backing materialcoating weights can be used while maintaining excellent tuft bind andabrasion resistance.

Examples 153-163

[0247] In another evaluation, tufted greige good samples were extrusioncoated to evaluate the effect of calcium carbonate as a high heatcontent filler and a conventional blowing agent (i.e., azodicarbonamide)when employed as an implosion agent. The calcium carbonate and theazodicarbonamide were dry-blended with a substantially linear ethylenepolymer according the weight percentage shown in the table immediatelybelow. The substantially linear ethylene polymer had 30 g/10 min. Meltindex and a 0.885 g/cc density and was supplied by The Dow ChemicalCompany under the designation XU-59400.00. The azodicarbonamideimplosion agent was Epicell #301 which was supplied as a 30 percentconcentrate in low density polyethylene by EPI Chemical Company. Thecalcium carbonate which had a specific heat capacity of about 0.548cal-cc/° C. (2.3 Joules-cm³/° C.) was supplied as a 75 percent weightconcentrate in low polyethylene by Heritage Bag Company.

[0248] Volunteer™ greige goods supplied by Shaw Industries was used inthis evaluation. The greige goods were polypropylene fibers, 26 oz/yd²(920 cm³/m²), tufted, loop pile, single stitch carpet swatches whichwere cut and slip sheeted onto Kraft paper for each sample such thateach example adhesive backing material was extrusion coated onto theback side of the carpet (i.e., onto the primary backing material of thecarpet swatches). For each sample, prior to extrusion coating on theadhesive backing material, the greige goods were first preheated in aconvection oven.

[0249] In this evaluation, the extrusion coating die configuration wasmonolayer and auxiliary equipment included pre-heaters and heat soakovens. Specifically, the extrusion coating equipment consisted of atwo-extruder Black Clawson coextrusion line with a 3½ inch (8.9 cm)diameter primary extruder with a 30:1 L/D and a 2½ inch (6.4 cm)diameter secondary extruder with a 24:1 L/D. However, in thisevaluation, only the large extruder was operated at variable rates. A 76cm slot die was attached to the extruder and deckled to 69 cm with a20-mil (0.51 mm) die gap and a 6-inch (15.2 cm) air/draw gap. The niproll pressure was set at 30 psi (0.2 MPa) and the chill roll temperaturewas varied. The greige goods pre-heat temperature was set at 160° F.(71° C.), the extrusion melt temperature was set at 550° F. (288° C.)and the line speed was 75 ft/min (23 m/min). The chill roll temperaturewas set at 100° F. (38° C.) for the sample that contained no implosionagent and was set at 70° F. for samples containing the implosion agent.

[0250] After the extrusion coated samples were aged for at least 24hours, they were tested for tuft bind, abrasion resistance, Velcrorating, fuzz rating, flexibility and delamination resistance. Tuft bindtesting was conducted using ASTM D-1335-67. Abrasion resistance andVelcro testing were based on qualitative tests wherein a 2 inch (51 mm)diameter, 2 pound (0.91 kg) roller coated with the loop side of standardVelcro was passed 10 times over the face side of each extrusion coatedsamples to abrade the sample. The fuzz on the abraded carpet was thencompared to a set of standards and rated on a 1-10 scale (10 denotingzero fuzz).

[0251] To provide quantitative abrasion results, a Fiber Lock Test wasused. In this test, the abrasion resistance value is taken as the “FiberLock Fuzz Number.” The test involves cutting away abraded fibers with apair of Fiskars 6″ spring-loaded scissors and comparing sample weightsbefore and after abraded fibers are removed. Specifically, the FiberLock Fuzz test is performed by providing 8 inches (203 mm) crossdirection×10 inches (254 mm) machine direction extrusion coated samples;clamping the samples such that they remain flat during double rolling;double rolling the samples in the machine direction 15 times at aconstant speed and at about a 450 angle using the Velcro rollerdiscussed above in this evaluation; using a 2 inches×2 inches (51 mm×51mm) sample cutter attached to a press punch certified by NationalAnalytical Equipment Federation (NAEF) to provide two test specimens foreach sample; weighing and recording the sample weights for each sampleto 0.1 mg using a calibrated AE200 balance; carefully removing allabraded fiber using a pair Fiskars 6″ spring-loaded scissors whileavoiding cutting any part of a fiber loop; reweighing and recording thetwo test samples; and taking the difference in weight before and afterremoval of the abraded fiber as the Fiber Lock Fuzz Number (FLFN). Notethat Fiber Lock Fuzz numbers relate inversely to Velcro Numbers; thatis, whereas higher Velcro numbers are desirable as indicative ofimproved abrasion resistance, lower Fuzz numbers indicate improvedabrasion resistance. Table 16provides the weight percentage of additiveand the carpet performance results. TABLE 16 Implosion Filler ResinCoating Filler Wt. Tuft Bind Velcro Fiber Agent Amount Wt.-oz/yd² oz/yd²lbs. Rating Lock Example % active % (cm³/m²) (cm³/m²) (kg) No. Fuzz No.153 0 0 9.3 NA 7.1 5 157 (329) (3.2) 154 0.5 0 10.0 NA 7.6 7 91 (354)(3.4) 155 1.0 0 9.4 NA 6.2 8 52 (332) (2.8) 156 1.5 0 9.7 NA 6.7 7 80(343) (3.0) 157 0 0 7.4 NA 8.1 3 261 (262) (3.7) 158 0 45 8.1 6.6 7.8 799 (286) (233) (3.5) 159 0 60 6.4 9.6 8.1 6 125 (226) (340) (3.7) 160 00 9.3 NA 7.1 3 261 (329) (3.2) 161 0.5 15 9.6 1.7 9.0 7 90 (340)  (60)(4.1) 162 0.5 30 8.9 3.9 8.7 7 108 (315) (138) (3.9) 163 0.5 45 8.0 6.67.5 8 73 (283) (233) (3.4)

[0252] All examples in this evaluation exhibited good flexibility andexamples with a Velcro number of at least 6 all exhibited gooddelamination resistance. The examples wherein the implosion agent wasused all had closed cells and a collapsed adhesive backing materialmatrix i.e., the thickness of the adhesive backing material layer wasabout same with and without the implosion agent. Table 16 shows that theuse an implosion agent and a high heat content filler either separatelyor in combination significantly improves both the tuft bind and abrasionresistance of extrusion coated carpet compared to an equivalent coatingweight of resin without these additives. Also, Table 16 surprisinglyindicates that the use of these additives allow improved performance atreduced adhesive backing material coat weights.

Examples 164-175

[0253] In another evaluation, an unmodified control adhesive backingmaterial sample and two adhesive backing material samples modified bythe addition of maleic anhydride grafted ethylene polymer were extrusioncoated onto tufted greige goods using a monolayer die configuration,although a single die coextrusion and dual lip coextrusion can also beused. Auxiliary equipment included: pre-heaters and heat soak ovens.

[0254] The extrusion coating equipment consisted of a two-extruder BlackClawson coextrusion line with a 3½ inch (8.9 cm) diameter primaryextruder with a 30:1 L/D and a 2½ inch (6.4 cm) diameter secondaryextruder with a 24:1 L/D. For these examples, only the large extruderwas operated at variable rates. A 76 cm slot die was attached anddeckled to 69 cm with a 20 mil ((0.51 mm) die gap and a 6 inch (15.2 cm)air/draw gap. The nip roll pressure was set at 30 psi, the chill rolltemperature was set at 75-80° F. (24-27° C.) and the extrusion linespeed was at 75 ft/min (23 m/min). Prior to application of the adhesivebacking material, the greige goods were pre-heated to about 210° F. (99°C.)in a convection oven and the extrusion melt temperature was 595-610°F. (313-321° C.).

[0255] The unmodified control adhesive backing material was asubstantially linear ethylene polymer having 30 g/10 min. melt index anda 0.885 g/cc density as supplied by The Dow Chemical Company under thedesignation XU-59400.00. To prepare two modified adhesive backingmaterials, XU-59400.00 was dry-blended with 10 weight percent of twodifferent maleic anhydride/ethylene polymer grafts, each containing 1.0weight percent maleic anhydride, to provide a final concentration of 0.1weight percent maleic anhydride for the two blends. The graftsthemselves were prepared following procedures described in U.S. Pat. No.4,762,890. One graft designated MAH-1 in Table 17, utilized a highdensity polyethylene as the host ethylene polymer. The other graft,designated MAH-2 in Table 17, utilized a substantially linear ethylenepolymer as the host ethylene polymer.

[0256] The greige goods were swatches of Vocation 26™ carpet supplied byShaw Industries. Vocation 26™ carpet consists of nylon fibers at 26oz/yd² (907 cm³/m²)and is characterized as a tufted, loop pile, singlestitch carpet. The greige good samples were slip sheeted onto Kraftpaper during extrusion coating to apply the control adhesive backingmaterial and the two modified adhesive backing materials. No secondarybacking material was added to the backside of the samples afterapplication of the adhesive backing materials, although such can also beused.

[0257] After the extrusion coated samples were allowed to age for atleast 24 hours at ambient room temperature, tuft bind, abrasionresistance and delamination performance were measured. Tuft bind testingwas conducted according to ASTM D-1335-67. Abrasion resistance resultswere obtained using the Velcro test procedure described above wherein a2 inch (51 mm) diameter, 2 pound (0.91 kg) roller coated with the loopside of standard Velcro was passed 10 times over the face side of coatedcarpet samples. The fuzz on the abraded carpet was then compared to aset of carpet standards and rated on a 1-10 scale (10 denoting zerofuzz). Abrasion resistance was also quantified using the Fiber Lock Testdescribed above. In general, if the Velcro Number was below 6 or theabrasion resistance of the carpet sample was rated poor, tuft binds werenot measured. The following Table 17 summarizes the results of thisevaluation. TABLE 17 Resin Coating MAH Wt.-oz/yd² Tuft Bind VelcroRating Fiber Lock Example Type (cm³/m²) lbs. Number. Fuzz No. 164 None3.7 (131) 5.3 6 148 165 None 4.9 (173) 5.2 6 161 166 None 6.0 (212) 5.64 218 167 None 8.7 (308) 7.3 6 136 168 MAH-1 3.4 (120) 5.2 5 197 169MAH-1 4.9 (173) 7.0 5 131 170 MAH-1 6.4 (226) 8.4 7 102 171 MAH-1 8.7(308) 9.0 7 93 172 MAH-2 3.6 (127) 5.7 5 200 173 MAH-2 5.2 (184) 5.5 6128 174 MAH-2 7.9 (279) 9.1 7 81 175 MAH-2 8.6 (304) 8.2 7 110

[0258] The results in Table 17 show that the incorporation of maleicanhydride ethylene polymer grafts, wherein either a high densitypolyethylene (HDPE) or a substantially linear ethylene polymer isemployed as the host resin, permit significant improvements incomparative tuft bind strength and abrasion resistance. One advantage ofthese improvements is now practitioners can employ reduced thermoplasticadhesive backing material coat weights for purposes of cost-savings andstill maintain desired levels of high performance.

Examples 176-181

[0259] Example 176 was the same as example 88 above except that therewas no adhesive backing extruded onto the carpet. The carpet thusproduced had good bundle penetration and wrap. Measurements showed thatabout 12 OSY (424 cm³/m²) of the FN500, based on dry weight, were addedto the carpet backing. The carpet was also tested according to testmethod ASTM D1335 to measure the tuft bind strength of the carpet (See,1991 Annual Book of ASTM Standards, Volume 07.01). This test measuresthe force required to pull one or both legs of a loop in a loop pilecarpet free from the backing. The carpet made in Example 176 showed anaverage tuft bind strength of 9.0 pounds (4.1 kg).

[0260] Example 177 was the same as example 176 except for the followingchanges: First, a defoamer was not used in the dispersion. SecondAerosil A300 from Degussa was added to the dispersion at 0.5 parts.Third, an HDPE from Dow Chemical Co. under the designation DOW 12065HDPE was used in the place of FN500. Fourth, a surfactant under thedesignation DA-6 from Sun Chemical International was used in place ofthe CO-430. Finally, the carpet was dried in a Blue M forced airconvection oven at 270° F. (132° C.) for 30 minutes. The add-on for theHDPE was 8.6 OSY (304 cm³/m²). The average tuft bind strength wasmeasured at 4.0 pounds (1.8 kg).

[0261] Example 178 was the same as example 177 except that the AerosilA-300 was removed and that, instead of the HDPE, an ethylene vinylacetate (EVA) polymer from Quantum under the designation FE-532. Theadd-on for the EVA was 10 OSY (354 cm³/m²). The average tuft bindstrength for the resulting carpet was measured at 8.2 pounds (3.7 kg).

[0262] Example 179 was the same as example 178 except that, instead ofthe EVA, a polyethylene from Quantum under the designation MRL-0414 wasused. The add-on for the polyethylene was 3 OSY (106 cm³/m²) and theaverage tuft bind strength was measured at 2.3 pounds (1.04 kg).

[0263] Example 180 was the same as example 177 except that add-on forthe FN500 was 5.4 OSY (191 cm³/m²). The tuft bind strength was measuredat 5.2 pounds (2.4 kg).

[0264] Example 181 was the same as example 180 except that, instead ofthe Igepal CO430, a surfactant under the designation OT-75 from SunChemical International was used. The add-on for the FN500 was 10.5 OSY(371 cm³/m²) and the average tuft bind strength was 4.3 pounds (1.95kg).

Examples 182-193

[0265] Examples 182-193 were performed to demonstrate differentsecondary backings applied to the carpet made in Example 176.

[0266] In Example 182, a piece of carpet made in Example 176 received asecondary backing by placing a coextruded sheet of ethylene vinylacetate/polyethylene from Quantum Chemical Co. under the designationNA202 UE635 on top of the non-pile side of the carpet. The pre-extrudedsheet was 23 mil (0.58 mm) thick. The carpet was then placed in agravity convection oven set at 300° F. (149° C.) for 30 minutes so as tocause the sheet to melt and bond to the back of the precoated carpet.The carpet was then allowed to cool to ambient temperatures.

[0267] Examples 183-185 were performed the same as Example 182 with theexception that the sheet of Quantum NA202 UE635 was 35, 37 and 50 mil(0.89, 0.94 and 1.3 mm) thick, respectively.

[0268] Example 186 was performed by taking the carpet from Example 176and applying a calcium carbonate filled VAE latex over the back of thecarpet. The carpet was then placed in a gravity convection oven at 300°F. (149° C.) for 30 minutes to dry the VAE. The coating weight was about25 OSY (884 cm³/m²), based on dry weight.

[0269] Example 187 was performed the same as Example 186 except that thelatex was an unfilled VAE latex. In particular, this latex was purchasedfrom Reichold Chemical Co. under the designation Elvace 97808.

[0270] Example 188 was performed the same as Example 186 with theexception that a calcium carbonate filed Styrene Butadiene Rubber (SBR)latex was used in place of the VAE latex. The SBR latex was applied soas to a coating weight of about 25 OSY (884 cm³/m²).

[0271] Example 189 was performed by taking carpet from Example 176 andspreading an EVA powder on the back of the carpet. In particular, theEVA powder was from DuPont under the designation Elvax 410 and wasapplied at 10 OSY (354 cm³/m²).

[0272] Example 190 was performed the same as Example 189 with theexception that the powder was a polyolefin wax supplied by Herculesunder the designation Polywvax 2000.

[0273] Example 191 was performed by taking the carpet from Example 176and applying a compounded hot melt adhesive to the back of the carpet.In particular, the hot melt consisted of filled EVA and Piccovar CB-20from Hercules, Inc. and was applied to the carpet at 30 OSY (1,061cm³/m²) and at a temperature of about 300° F. (149° C.).

[0274] Example 192 was performed the same as Example 191 with theexception that a urethane foam pad was laminated to the carpet backingthrough the hot melt. In particular, a polyurethane foam pad, availablefrom Shaw Industries under the designation Duratech 100, was laminatedwith the hot melt.

[0275] Example 193 was performed in accordance with the preferredembodiment of the aqueous pre-coat aspect of the present invention. Asample of carpet from Example 176 had a sheet of a polymer extrudeddirectly onto the back. The polymer used was the polyethylene elastomerprovided designated “G” in Table 1 above. The density of this particularpolymer was about 0.90 g/cc. The melt index was 75.

[0276] A Marsden propane fired infrared heater was used to preheat thesubstrate. The heater was set at temperatures between about 200° F. (93°C.) and about 230° F. (110° C). The temperature of the carpet wasmeasured at about 145° F. (63° C.) at the point just prior to receivingthe extruded sheet. The polymer was extruded at a 7 mil (0.18 mm)thickness using a typical extrusion coating setup used for papercoating. In particular, a typical polyethylene type extruder was usedwith temperatures of 350° F. (177° C.) for the first barrel, 375° F.(191° C.) for the second barrel and 400° F. (204° C.) for the remainingbarrels, the manifold and the extrusion die. The die was a slot typethat extruded a curtain of hot polymer onto the back of the carpet. Thecarpet was then placed around a chill roll with the back against thechill roll and with a temperature of 120° F. (49° C.). The line speedwas set to 23 feet per minute (7 m/min). The carpet was pressed at thechill roll with a nip pressure of 45 psi (0.31 MPa). Although not donein this specific example, a fabric, such as a typical polypropylenesecondary backing fabric from Amoco Fabrics & Fibers as “ActionBac®,”can be laminated through the extruded sheet just prior to or at thischill roll.

Examples 194-197

[0277] Examples 194-197 were conducted to make carpet tile according tothe present invention.

[0278] Example 194 was carried out in accordance with the most preferredmethod of making carpet tile. A 6 ft. (1.8 m) wide greige good wasprovided in a roll. The greige good comprised polypropylene yarn tuftedinto a non-woven primary backing obtained from Akzo under the name“Colback” (a blend of polyamide and polyester polymers) as cut pile at aface yarn weight of about 45 OSY (1,592 cm³/m²). This greige good waspassed below the extruder at 17 feet per minute (5.2 m/min). Theextruder contained a molten polymer mix having the followingcomposition: % by wt. Substantially linear ethylene polymer 24(XU-59400.00 from Dow) Maleic Anhydride Grafted Polyethylene  4(XU-60769.07 from Dow) Calcium Carbonate Filler (Georgia 59 Marble #9)Tackifier (Hercatac 1148 from 12 Hercules) Black Concentrate  1 100 

[0279] The temperature at the die was about 500° F. About 25 OSY (884cm³/m²) was applied in a first pass, after which a sheet of areinforcement fabric was laid on top of this first layer of polymer. Thereinforcement fabric in this example was a 3.5 OSY (124 cm³/m²) sheet ofTypar (a non-woven polypropylene fabric available from Reemay as“3351”). After passing over a chill roll, the carpet was rolled up for asubsequent pass through the line to apply a second layer.

[0280] In a second pass through the same line, a second layer of thesame extrudate was applied on top of the reinforcement sheet. The totaladd-on, not including the Typar was 49.2 OSY (1,740 cm³/m²).

[0281] After cooling, the carpet was cut into 18 inches (45.7 cm) squaretiles and tested for Tuft bind, and Aachen dimensional stability. Theresults are shown in the Table 18 below.

[0282] Example 195 was performed the same as Example 194 except that aloop pile nylon yarn was used for the face yarn at 20 OSY (707 cm³/m²)with a straight stitch and the total add-on was 54.0 OSY (1,910 cm³/m²).

[0283] Example 196 was performed the same as Example 195 except that theloop pile nylon yarn was tufted at 30 OSY (1,061 cm³/m²) with a shiftedstitch and the total add-on was 52.6 OSY (1,860 cm³/m²).

[0284] Example 197 was performed the same as Example 196 except that theprimary backing used was a non-woven polyester fabric sold byFreudenberg as “Lutradur.” The total add-on was 52.3 OSY (1,850 cm³/m²).TABLE 18 Add-On OSY Tuft bind* Aachen M Aachen XM Ex # Face Fiber(cm³/m²) lbs. (kg) (% change) (% change) 194 PP 49.2 2.9 −0.023 0.105(1,740) (1.3) 195 Nylon 54.0 4.6 −0.062 0.144 (1,910) (2.1) 196 Nylon526 4.2 −0.054 −0.054 (1,860) (1.9) 197 Nylon 52.3 4.7 0.063 0.091(1,850) (2.1)

Examples 198-208

[0285] Examples 198-208 were conducted to make carpet tile withdifferent add-on weights for the second pass. In addition, two differentreinforcement materials were tests.

[0286] Example 198 was performed the same as Example 194 above with theexception that the extrudate applied in the first pass had the followingcomposition: % by wt. Substantially linear ethylene polymer 69(XU-59400.00 from Dow) Calcium Carbonate Filler (Georgia 30 Marble #9)Black Concentrate  1 100 

[0287] 11 OSY (389 cm³/m²) of this extrudate was applied to the back ofa greige good that consisted of a polypropylene yarn tufted into a wovenpolypropylene primary backing at about 26 OSY (920 cm³/m²) in a looppattern.

[0288] In Examples 198-203, a 3.5 OSY (124 cm³/m²) Typar fabric wasembedded between the first layer of extrudate and the second. InExamples 204-208, a 1.4 OSY (49.5 cm³/m²) fiberglass scrim from ELKCorp. was used as the reinforcement layer.

[0289] In all of Examples 198-208, the second layer of extrudate, whichwas put on in a second pass through the same line, had the followingcomposition: % by wt. Substantially linear ethylene polymer 24(XU-59400.00 from Dow) Maleic Anhydride Grafted Polyethylene  4(XU-60769.07 from Dow) Calcium Carbonate Filler (Georgia 59 Marble #9)Tackifier (Hercatac 114876 from 12 Hercules) Black Concentrate  1 100 

[0290] The add-on weight from the second pass was varied as shown belowin Table 19. The carpet was cut into tiles and subjected to the Aachendimensional stability test with the results noted below. TABLE 19Reinforce-ment 2^(nd) Pass Total OSY Add-On, OSY Add-On, OSY Aachen MAachen XM Ex. # (cm³/m³) (cm³/m³) (cm³/m³) (% change) (% change) 198Typar 3.5 (124) 29.7 (1,050) 40.7 (1,440) .059 .061 199 Typar 3.5 (124)30.5 (1,079) 41.5 (1,468) .044 .100 200 Typar 3.5 (124) 39.3 (1,390)50.3 (1,779) −.064 .075 201 Typar 3.5 (124) 44.0 (1,556) 55.0 (1,945)−.106 .014 202 Typar 3.5 (124) 47.5 (1,680) 58.5 (2,069) 0 .044 203Typar 3.5 (124) 56.0 (1,981) 67.0 (2,370) .003 .067 204 f.g. 1.4 (50)41.6 (1,471) 52.6 (1,860) .083 .070 205 f.g. 1.4 (50) 47.3 (1,673) 58.3(2,062) .086 .014 206 f.g. 1.4 (50) 52.3 (1,850) 63.3 (2,239) .003 .086207 f.g. 1.4 (50) 54.1 (1,914) 65.1 (2,303) .044 .014 208 f.g. 1.4 (50)58.4 (2,066) 69.4 (2,455) .025 .019

[0291] While particular preferred and alternative embodiments have beendescribed herein, it should be noted that various other embodiments andmodifications can be made without departing from the scope of theinventions described herein. It is the appended claims which define thescope of the patent issuing from the present application.

What is claimed is:
 1. A method of making a carpet, the carpetcomprising (i) a plurality of fibers attached to a primary backingmaterial having a face and a back side and (ii) an adhesive backingmaterial which comprises at least one homogeneously branched ethylenepolymer characterized as having a single melt point as measured bydifferential scanning calorimetry (DSC) between −30 and 140° C. and ashort chain branching distribution index (SCBDI) of greater than orequal to 50 percent and which is in intimate contact with the back sideof the primary backing material and has substantially penetrated andsubstantially consolidated the fibers, the method comprising extrusioncoating the adhesive backing material onto the back side of the primarybacking material and at least one additional step selected from thegroup consisting of (a) preheating the primary backing material prior tothe application of the adhesive backing material, (b) during theextrusion coating of the adhesive backing material, while at atemperature greater than or equal to the softening point of the adhesivebacking material, subjecting the adhesive backing material to a vacuumto draw the adhesive backing material onto the back side of the primarybacking material, (c) during the extrusion coating of the adhesivebacking material, while at a temperature greater than or equal to thesoftening point of the adhesive backing material, subjecting theadhesive backing material to a positive air pressure device in additionto nip roll pressure to force the adhesive backing material onto theback side of the primary backing material, and (d) heat soaking thecarpet after application of the adhesive backing material onto the backside of the primary backing material.
 2. A carpet comprising a primarybacking material having a face and a back side, a plurality of fibersattached to the primary backing material and extending from the face ofthe primary backing material and exposed at the back side of the primarybacking material, an adhesive backing material and an optional secondarybacking material adjacent to the adhesive backing material, wherein theadhesive backing material comprises at least one homogeneously branchedethylene polymer characterized as having a single melt point as measuredby differential scanning calorimetry (DSC) between −30 and 140° C. and ashort chain branching distribution index (SCBDI) of greater than orequal to 50 percent and is in intimate contact with the back surface ofthe primary backing material and has substantially penetrated andconsolidated the fibers, and wherein the adhesive backing material oroptional secondary backing material is comprised of an effective amountof at least one additive selected from the group consisting of a blowingagent and high heat content filler with the proviso that where theblowing agent is selected, the adhesive backing material or the optionalsecondary backing material is further characterized as having asubstantially foamed, frothed or expanded non-collapsed matrix.
 3. Amethod of making a carpet, the carpet comprising yarn attached to aprimary backing material having a back side and an adhesive backingmaterial, the adhesive backing material comprises at least onehomogeneously branched ethylene polymer characterized as having a singlemelt point as measured by differential scanning calorimetry (DSC) at −30and 140° C. and a short chain branching distribution index (SCBDI) ofgreater than or equal to 50 percent, and wherein the adhesive backingmaterial is in intimate contact with the back surface of the primarybacking material and has substantially penetrated and substantiallyconsolidated the yarn, the method comprising the step of adding aneffective amount of a high heat content filler to the adhesive backingmaterial to enhance the penetration of the adhesive backing materialinto the yarn.
 4. A method of making a carpet, the carpet comprisingyarn attached to a primary backing material having a face and a backside and an adhesive backing material comprised of at least one firstand at least one second ethylene polymer layers, wherein the firstethylene polymer layer is in intimate contact with the back surface ofthe primary backing material, has substantially penetrated andsubstantially consolidated the yarn, and has a higher melt index thanthe second ethylene polymer layer, the method comprising the steps ofapplying the first ethylene polymer layer directly onto the back side ofthe primary backing material and simultaneously or sequentially applyingthe second ethylene polymer layer onto the first ethylene polymer layer.5. The method of claim 4 wherein both the first and second ethylenepolymer layers comprise a non-polar ethylene polymer.
 6. The method ofclaim 4 wherein one of the first or second ethylene polymer layerscomprise an adhesive polymer.
 7. A method of making carpet comprisingthe steps of: providing a primary backing material; tufting a yarn intothe primary backing material to produce a carpet pile on the front sideof the primary backing material and loops of the yarn on the back sideof the primary backing material; providing an aqueous dispersion ofpolyolefin particles; applying the dispersion to the back side of theprimary backing material; applying heat to the dispersion to dry thedispersion and to at least partially melt the polyolefin particles andthereby fix the loops of yarn to the primary backing material.
 8. Themethod of claim 7 wherein the particles are present in an amount betweenabout 25 and about 50 percent by weight of the dispersion.
 9. The methodof claim 7 wherein the average size of the particles is between about 1and about 1000 microns.
 10. The method of claim 9 wherein the particlescomprise polyethylene.
 11. The method of claim 10 wherein thepolyethylene has a melt index at 190° C. of between about 1 and about100.
 12. The method of claim 7 wherein the dispersion comprisesparticles of polypropylene.
 13. The method of claim 7 wherein thedispersion comprises particles of ethylene acrylic acid.
 14. The methodof claim 7 wherein the dispersion further comprises a surfactant. 15.The method of claim 7 wherein the dispersion further comprises athickener.
 16. The method of claim 7 wherein the step of applying heatis carried out in an oven at a temperature between about 100 and about150 ° C.
 17. The method of claim 16 wherein the temperature is betweenabout 5 and about 75° C. above the melting point of the thermoplasticparticles.
 18. The method of claim 7 wherein between about 6 and about12 ounces per square yard of the polyolefin particles are applied to theback side of the primary backing.
 19. The method of claim 7 wherein theyarn, the primary backing and the thermoplastic particles are all madefrom a polyolefin.
 20. The method of claim 7 further comprising the stepof applying an additional backing to the carpet by extruding a sheet ofa thermoplastic material to the back side of the primary backing afterthe applying heat step.
 21. The method of claim 20 wherein thethermoplastic material in the extruded sheet is selected from the groupconsisting of polyolefin, polyvinyl chloride, ethylene vinyl acetate,polyamide, polyester, and copolymers thereof.
 22. The method of claim 20wherein the thermoplastic material in the extruded sheet is athermoplastic elastomer.
 23. The method of claim 20 wherein thethermoplastic material in the extruded sheet is a homogeneously branchedethylene polymer characterized as having a single melt point as measuredby differential scanning calorimetry (DSC) between −30 and 140° C. and ashort chain branching distribution index (SCBDI) of greater than orequal to 50 percent.
 24. The carpet of claim 23 wherein thehomogeneously branched linear ethylene polymer is an interpolymer ofethylene with at least one C₃-C₂₀ a-olefin.
 25. The carpet of claim 23wherein the homogeneously branched linear ethylene polymer is acopolymer of ethylene and one C₃-C₂₀ a-olefin.
 26. The carpet of claim23 wherein the homogeneously branched linear ethylene polymer has adensity in the range about 0.86 g/cc to about 0.90 g/cc.
 27. The methodof claim 20 wherein the thermoplastic material in the extruded sheet isa polyolefin.
 28. The method of claim 20 wherein the yarn, the primarybacking, the thermoplastic polymers and the extruded sheet are all madefrom a polyolefin.
 29. The method of claim 7 further comprising the stepof applying an additional backing to the carpet by applying a layer ofadhesive to the back side of the primary backing and laminating asecondary backing material thereto.
 30. The method of claim 29 whereinthe adhesive and the secondary backing material are made from apolyolefin.
 31. The method of claim 7 further comprising the step ofapplying an additional backing to the carpet by applying a layer ofmelted polyolefin on the back side of the primary backing.
 32. Themethod of claim 7 further comprising the step of applying an additionalbacking to the carpet by casting a thermosettable material on the backside of the primary backing and then applying heat to set thethermosettable material.
 33. A carpet comprising: a primary backing witha face side and a back side, said primary backing being made from apolyolefin; polyolefin yarn tufted into the primary backing so as toproduce a carpet pile on the face side of the primary backing and loopsof yarn on the back side of the primary backing; polyolefin particlesthat have been at least partially melted around the loops of yarn on theback side of the primary backing to thereby bind the loops to the backside of the primary backing.
 34. The carpet of claim 33 furthercomprising a secondary backing attached to back side of the primarybacking, said secondary backing being made from a polyolefin.
 35. Thecarpet of claim 34 wherein the secondary backing is attached to theprimary backing through an extruded sheet of a polyolefin.
 36. Thecarpet of claim 35 wherein the primary and secondary backing are madefrom polypropylene and the polyolefin particles and the extruded sheetare made from polyethylene.
 37. The carpet of claim 36 wherein thecarpet further includes a label or literature at the time of sale whichrepresents that the carpet is recyclable without segregation of carpetcomponents.
 38. A method of making carpet comprising the steps of:providing a primary backing material; tufting a yarn into the primarybacking material to produce a carpet pile on the front side of theprimary backing material and loops of the yarn on the back side of theprimary backing material; extruding a first sheet of a firstthermoplastic material to the back side of the primary backing; andextruding a second sheet of a second thermoplastic material adjacent thefirst sheet; wherein the melt viscosity of the thermoplastic material inthe first sheet is lower than the melt viscosity of the thermoplasticmaterial in the second sheet so as to provide for enhanced penetrationof the thermoplastic material in the first sheet into at least one ofthe primary backing material or the loops of yarn on the back side ofthe primary backing material.
 39. The method of claim 38 wherein themelt index at 190° C. of the thermoplastic material in the first sheetis between about 30 and about 175 g/10 min. and the melt index at 190°C. of the thermoplastic material in the second sheet is below the meltindex of the thermoplastic material in the first sheet and is betweenabout 1 and about 70 g/10 min.
 40. The method of claim 38 wherein themelt index of the thermoplastic material in the first sheet is at leastabout 20 g/10 min. at 190° C. lower than the melt index of thethermoplastic material in the second sheet.
 41. The method of claim 38wherein the thermoplastic material in one of the extruded sheets is athermoplastic elastomer.
 42. The method of claim 38 wherein thethermoplastic material in one of the extruded sheets is a homogeneouslybranched ethylene polymer.
 43. The method of claim 38 wherein thethermoplastic material in the first and second extruded sheets is ahomogeneously branched ethylene.
 44. A carpet comprising: primarybacking material; yarn tufted into the primary backing material toproduce a carpet pile on the front side of the primary backing materialand loops of the yarn on the back side of the primary backing material;a first sheet of a thermoplastic material extruded on the back side ofthe primary backing; and a second sheet of a thermoplastic materialadjacent the first sheet; wherein the melt viscosity of thethermoplastic material in the first sheet is lower than the meltviscosity of the thermoplastic material in the second sheet so as toprovide for enhanced penetration of the thermoplastic material in thefirst sheet into at least one of the primary backing material or theloops of yarn on the back side of the primary backing material.
 45. Thecarpet of claim 44 wherein the melt index at 190° C. of thethermoplastic material in the first sheet is between about 30 and about175 g/10 min. and the melt index at 190° C. of the thermoplasticmaterial in the second sheet is below the melt index of thethermoplastic material in the first sheet and is between about 1 andabout 70 g/10 min.
 46. The carpet of claim 44 wherein the melt index ofthe thermoplastic material in the first sheet is at least about 20 g/10min. at 190° C. lower than the melt index of the thermoplastic materialin the second sheet.
 47. The carpet of claim 44 wherein thethermoplastic material in one of the extruded sheets is a thermoplasticelastomer.
 48. The carpet of claim 44 wherein the thermoplastic materialin one of the extruded sheets is a homogeneously branched ethylene. 49.The carpet of claim 44 wherein the thermoplastic material in the firstand second extruded sheets is a homogeneously branched ethylene polymer.50. A method of making carpet comprising the steps of: providing aprimary backing material; tufting a yarn into the primary backingmaterial to produce a carpet pile on the face side of the primarybacking material and loops of the yarn on the back side of the primarybacking material; heating the back side of the primary material; whilethe back side of the primary material is at an elevated temperature fromthe heating step, extruding a sheet of a thermoplastic material to theback side of the primary backing.
 51. The method of claim 50 where theback side of the primary backing is heated above at least about 140 ° F.52. The method of claim 50 wherein the thermoplastic material comprisesat least one homogeneously branched ethylene polymer.
 53. A method ofmaking carpet comprising the steps of: providing a primary backingmaterial; tufting a yarn into the primary backing material to produce acarpet pile on the face side of the primary backing material and loopsof the yarn on the back side of the primary backing material; extrudinga sheet of a thermoplastic material to the back side of the primarybacking; and while the sheet of thermoplastic material is still molten,applying a vacuum to the face side to thereby draw the moltenthermoplastic material onto the back side of the primary backing. 54.The method of claim 53 where the vacuum has a draw of at least about 15inches of H₂O.
 55. The method of claim 53 wherein the thermoplasticmaterial comprises at least one homogeneously branched ethylene polymer.56. A method of making carpet comprising the steps of: providing aprimary backing material; tufting a yarn into the primary backingmaterial to produce a carpet pile on the face side of the primarybacking material and loops of the yarn on the back side of the primarybacking material; extruding a sheet of a thermoplastic material to theback side of the primary backing; and while the sheet of thermoplasticmaterial is still molten, directing pressurized air toward the back sideto thereby push the molten thermoplastic material onto the back side ofthe primary backing.
 57. The method of claim 56 wherein the pressurizedair has a pressure of at least about 20 psi.
 58. The method of claim 56wherein the thermoplastic material comprises at least one homogeneouslybranched ethylene polymer.
 59. A method of making carpet comprising thesteps of: providing a primary backing material; tufting a yarn into theprimary backing material to produce a carpet pile on the face side ofthe primary backing material and loops of the yarn on the back side ofthe primary backing material; extruding a sheet of a thermoplasticmaterial to the back side of the primary backing; and applying heat tothe back side to thereby lengthen the time the extruded sheet ofthermoplastic material remains molten thus enhancing the penetration ofthe thermoplastic material on the back side.
 60. The method of claim 59where the heat is applied for at least about 3 seconds after extrusion.61. The method of claim 59 wherein the thermoplastic material comprisesat least one homogeneously branched ethylene polymer.
 62. A method ofmaking carpet comprising the steps of: providing a primary backingmaterial; tufting a yarn into the primary backing material to produce acarpet pile on the face side of the primary backing material and loopsof the yarn on the back side of the primary backing material; extrudinga sheet of a thermoplastic material to the back side of the primarybacking; prior to the extruding step, treating at least the back side ofthe primary backing and loops of the yarn on the back side of theprimary backing to remove undesirable chemicals from the surface andthereby enhance the adhesion of the extruded sheet.
 63. The method ofclaim 62 wherein the treating step includes an aqueous washing.
 64. Themethod of claim 62 wherein the thermoplastic material comprises at leastone homogeneously branched ethylene polymer.
 65. A method of makingcarpet comprising the steps of: providing a primary backing material;tufting a yarn into the primary backing material to produce a carpetpile on the face side of the primary backing material and loops of theyarn on the back side of the primary backing material; and extruding amolten sheet of a thermoplastic material to the back side of the primarybacking; and allowing the sheet of a thermoplastic material to solidifyto thereby fix the loops of the yarn to the back side of the primarybacking; wherein the sheet of thermoplastic material includes aninorganic filler having a specific heat and in an amount sufficient tolengthen the solidification time of the molten sheet and thereby enhancepenetration of the thermoplastic material.
 66. The method of claim 65wherein the inorganic filler is selected from the group consisting ofcalcium carbonate, barium sulfate, aluminum trihydrate, and talc,together with mixtures thereof.
 67. The method of claim 65 wherein theinorganic filler calcium carbonate.
 68. The method of claim 65 whereinthe inorganic filler is present at between about 1 and about 75 weightpercent of the thermoplastic material in the extruded sheet.
 69. Amethod of making carpet comprising the steps of: providing a primarybacking material; tufting a yarn into the primary backing material toproduce a carpet pile on the face side of the primary backing materialand loops of the yarn on the back side of the primary backing material;extruding a molten sheet of a thermoplastic material to the back side ofthe primary backing, wherein the sheet of thermoplastic materialincludes an effective amount of at least one blowing agent; andactivating the at least one blowing agent to expand the thermoplasticmaterial.
 70. The method of claim 69 wherein the inorganic filler isselected from the group consisting of calcium carbonate, barium sulfate,aluminum trihydrate, and talc, together with mixtures thereof.
 71. Themethod of claim 69 wherein the inorganic filler calcium carbonate. 72.The method of claim 69 wherein the inorganic filler is present atbetween about 1 and about 75 weight percent of the thermoplasticmaterial in the extruded sheet.
 73. A method of making carpet comprisingthe steps of: providing a primary backing material; tufting a yarn intothe primary backing material to produce a carpet pile on the front sideof the primary backing material and loops of the yarn on the back sideof the primary backing material; extruding a sheet of a firstthermoplastic material to the back side of the primary backing; andlaminating a secondary backing material to the extruded sheet; whereinthe secondary backing comprises a material with fibers protrudingtherefrom to thereby enhance adhesion of the carpet to a floor.
 74. Themethod of claim 73 wherein the secondary backing comprises a woven ornon-woven fabric with fibers needle-punched therein.
 75. The method ofclaim 74 wherein the secondary backing includes between about 0.5 andabout 3 oz. of fibers per yard of secondary backing.
 76. The method ofclaim 74 wherein the fibers comprise polypropylene.
 77. The method of 73wherein the secondary backing comprises a spun-bond non-woven fabric.78. A method of making carpet comprising the steps of: providing aprimary backing material; tufting a yarn into the primary backingmaterial to produce a carpet pile on the front side of the primarybacking material and loops of the yarn on the back side of the primarybacking material; extruding a sheet of a first thermoplastic material tothe back side of the primary backing; and laminating a secondary backingmaterial to the extruded sheet, said secondary backing comprising a lenoweave fabric with monofilament strands in the machine and crossdirections.
 79. The method of claim 78 wherein the secondary backing ismade of polypropylene.
 80. A carpet comprising a primary backingmaterial having a face and a back side, a plurality of fibers attachedto the primary backing material and extending from the face of theprimary backing material and exposed at the back side of the primarybacking material, an adhesive backing material and an optional secondarybacking material adjacent to the adhesive backing material, wherein theadhesive backing material comprises at least one homogeneously branchedlinear ethylene polymer characterized as having a single melt point asmeasured by differential scanning calorimetry (DSC) between −30 and 140°C. and a short chain branching distribution index (SCBDI) of greaterthan or equal to 50 percent and is in intimate contact with the backsurface of the primary backing material and has substantially penetratedand consolidated the fibers, and wherein the adhesive backing materialor optional secondary backing material is comprised of an effectiveamount of at least one additive selected from the group consisting of ablowing agent and high heat content filler with the proviso that wherethe blowing agent is selected, the adhesive backing material or theoptional secondary backing material is further characterized as having asubstantially foamed, frothed or expanded non-collapsed matrix.
 81. Amethod of making a carpet, the carpet comprising yarn attached to aprimary backing material having a back side and an adhesive backingmaterial, the adhesive backing material comprises at least onehomogeneously branched ethylene polymer characterized as having a singlemelt point as measured by differential scanning calorimetry (DSC) at −30and 140° C. and a short chain branching distribution index (SCBDI) ofgreater than or equal to 50 percent, and wherein the adhesive backingmaterial is in intimate contact with the back surface of the primarybacking material and has substantially penetrated and substantiallyconsolidated the yarn, the method comprising the step of adding aneffective amount of a high heat content filler to the adhesive backingmaterial to enhance the penetration of the adhesive backing materialinto the yarn.
 82. The method of claim 81 wherein the inorganic filleris selected from the group consisting of calcium carbonate, bariumsulfate, aluminum trihydrate, and talc, together with mixtures thereof.83. The method of claim 81 wherein the inorganic filler calciumcarbonate.
 84. The method of claim 81 wherein the inorganic filler ispresent at between about 1 and about 75 weight percent based on thetotal weight of the at least one homogeneously branched ethylenepolymer.
 85. A method of making a carpet, the carpet having a foamed,frothed or expanded adhesive backing material and comprising yarnattached to a primary backing material having a face and back side, theadhesive backing material comprising at least one ethylene polymer andis in intimate contact with the back side of the primary backingmaterial and has substantially penetrated and substantially consolidatedthe yarn, the method comprising the step of adding an effective amountof at least one blowing agent to the adhesive backing material andthereafter activating the blowing agent to foam, froth or expand theadhesive backing material.
 86. The method of claim 85 wherein the atleast one ethylene polymer is a homogeneously branched linear ethylenepolymer.
 87. The method of claim 86 wherein the homogeneously branchedlinear ethylene polymer is an interpolymer of ethylene with at least oneC₃-C₂₀ a-olefin.
 88. The method of claim 87 wherein the C₃-C₂₀ a-olefinis selected from the group consisting of propylene, 1-butene,1-isobutylene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-heptene and1-octene.
 89. The method of claim 86 wherein the homogeneously branchedlinear ethylene polymer is characterized as having a single melt pointas measured by differential scanning calorimetry (DSC) between −30 and140° C. and a short chain branching distribution index (SCBDI) ofgreater than or equal to 50 percent.
 90. The method of claim 89 whereinthe homogeneously branched linear ethylene polymer has a density in therange about 0.86 g/cc to about 0.90 g/cc.
 91. A method of making carpetcomprising the steps of: providing a primary backing material; tufting ayarn into the primary backing material to produce a carpet pile on theface side of the primary backing material and loops of the yarn on theback side of the primary backing material; extruding a molten sheet of athermoplastic material to the back side of the primary backing, whereinthe sheet of thermoplastic material includes an effective amount of atleast one blowing agent; and activating the at least one blowing agentto expand the thermoplastic material.
 92. The method of claim 91 whereinthe thermoplastic material is a homogeneously branched linear ethylenepolymer.
 93. The method of claim 92 wherein the homogeneously branchedlinear ethylene polymer has a density in the range about 0.86 g/cc toabout 0.90 g/cc.
 94. A carpet comprising a primary backing materialhaving a face and a back side, a plurality of fibers attached to theprimary backing material and extending from the face of the primarybacking material and exposed at the back side of the primary backingmaterial, an adhesive backing material and an optional secondary backingmaterial adjacent to the adhesive backing material, wherein the adhesivebacking material comprises at least one substantially linear ethylenepolymers characterized as having (a) a melt flow ratio, I₁₀/I₂ ³ 5.63,(b) a molecular weight distribution, M_(w)/M_(n), as determined by gelpermeation chromatography and defined by the equation: (M _(w) /M_(n))≦(I ₁₀ /I ₂)−4.63, (c) a gas extrusion rheology such that thecritical shear rate at onset of surface melt fracture for thesubstantially linear ethylene polymer is at least 50 percent greaterthan the critical shear rate at the onset of surface melt fracture for alinear ethylene polymer, wherein the linear ethylene polymer has ahomogeneously branched short chain branching distribution and no longchain branching, and wherein the substantially linear ethylene polymerand the linear ethylene polymer are simultaneously ethylene homopolymersor interpolymers of ethylene and at least one C₃-C₂₀ a-olefin and haveessentially the same I₂ and M_(w)/M_(n) and wherein the respectivecritical shear rates of the substantially linear ethylene polymer andthe linear ethylene polymer are measured at the same melt temperatureusing a gas extrusion rheometer, (d) a single differential scanningcalorimetry, DSC, melting peak between −30 and 140° C., and (e) a shortchain branching distribution index (SCBDI) of greater than or equal to50 percent and is in intimate contact with the back surface of theprimary backing material and has substantially penetrated andconsolidated the fibers, and wherein the adhesive backing material oroptional secondary backing material is comprised of an effective amountof at least one additive selected from the group consisting of a blowingagent and high heat content filler with the proviso that where theblowing agent is selected, the adhesive backing material or the optionalsecondary backing material is further characterized as having asubstantially foamed, frothed or expanded non-collapsed matrix.
 95. Amethod of making a carpet, the carpet comprising yarn attached to aprimary backing material having a back side and an adhesive backingmaterial, the adhesive backing material comprises at least onesubstantially linear ethylene polymers characterized as having (a) amelt flow ratio, I₁₀/I₂ ³ 5.63, (b) a molecular weight distribution,M_(w)/M_(n), as determined by gel permeation chromatography and definedby the equation: (M _(w) /M _(n))≦(I₁₀ /I ₂)−4.63, (c) a gas extrusionrheology such that the critical shear rate at onset of surface meltfracture for the substantially linear ethylene polymer is at least 50percent greater than the critical shear rate at the onset of surfacemelt fracture for a linear ethylene polymer, wherein the linear ethylenepolymer has a homogeneously branched short chain branching distributionand no long chain branching, and wherein the substantially linearethylene polymer and the linear ethylene polymer are simultaneouslyethylene homopolymers or interpolymers of ethylene and at least oneC₃-C₂₀ a-olefin and have essentially the same I₂ and M_(w)/M_(n) andwherein the respective critical shear rates of the substantially linearethylene polymer and the linear ethylene polymer are measured at thesame melt temperature using a gas extrusion rheometer, (d) a singledifferential scanning calorimetry, DSC, melting peak between −30 and140° C., and (e) a short chain branching distribution index (SCBDI) ofgreater than or equal to 50 percent, and wherein the adhesive backingmaterial is in intimate contact with the back surface of the primarybacking material and has substantially penetrated and substantiallyconsolidated the yarn, the method comprising the step of adding aneffective amount of a high heat content filler to the adhesive backingmaterial to enhance the penetration of the adhesive backing materialinto the yarn.
 96. The method of claim 95 wherein the inorganic filleris selected from the group consisting of calcium carbonate, bariumsulfate, aluminum trihydrate, and talc, together with mixtures thereof.97. The method of claim 95 wherein the inorganic filler calciumcarbonate.
 98. The method of claim 95 wherein the inorganic filler ispresent at between about 1 and about 75 weight percent based on thetotal weight of the at least one substantially linear ethylene polymer.99. A method of making a carpet, the carpet having a foamed, frothed orexpanded adhesive backing material and comprising yarn attached to aprimary backing material having a face and back side, the adhesivebacking material comprising at least one ethylene polymer and is inintimate contact with the back side of the primary backing material andhas substantially penetrated and substantially consolidated the yarn,the method comprising the step of adding an effective amount of at leastone blowing agent to the adhesive backing material and thereafteractivating the blowing agent to foam, froth or expand the adhesivebacking material.
 100. The method of claim 99 wherein the at least oneethylene polymer is a substantially linear ethylene polymerscharacterized as having (a) a melt flow ratio, I₁₀/I₂ ³ 5.63, (b) amolecular weight distribution, M_(w)/M_(n), as determined by gelpermeation chromatography and defined by the equation: (M _(w) /M_(n))≦(I ₁₀ /I ₂)−4.63, (c) a gas extrusion rheology such that thecritical shear rate at onset of surface melt fracture for thesubstantially linear ethylene polymer is at least 50 percent greaterthan the critical shear rate at the onset of surface melt fracture for alinear ethylene polymer, wherein the linear ethylene polymer has ahomogeneously branched short chain branching distribution and no longchain branching, and wherein the substantially linear ethylene polymerand the linear ethylene polymer are simultaneously ethylene homopolymersor interpolymers of ethylene and at least one C₃-C₂₀ a-olefin and haveessentially the same I₂ and M_(w)/M_(n) and wherein the respectivecritical shear rates of the substantially linear ethylene polymer andthe linear ethylene polymer are measured at the same melt temperatureusing a gas extrusion rheometer, (d) a single differential scanningcalorimetry, DSC, melting peak between −30 and 140° C., and (e) a shortchain branching distribution index (SCBDI) of greater than or equal to50 percent.
 101. The method of claim 100 wherein the substantiallylinear ethylene polymer is an interpolymer of ethylene with at least oneC₃-C₂₀ a-olefin.
 102. The method of claim 100 wherein the substantiallylinear ethylene polymer is a copolymer of ethylene and 1-octene. 103.The method of claim 101 wherein the at least one C₃-C₂₀ a-olefin isselected from the group consisting of propylene, 1-butene,1-isobutylene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-heptene and1-octene.
 104. The method of claim 103 wherein the substantially linearethylene polymer has a density in the range about 0.86 g/cc to about0.90 g/cc.
 105. A method of making carpet comprising the steps of:providing a primary backing material having a face and a back side;tufting a yarn into the primary backing material to produce a carpetpile on the face side of the primary backing material and loops of theyarn on the back side of the primary backing material; extruding amolten sheet of a thermoplastic material to the back side of the primarybacking, wherein the sheet of thermoplastic material includes aneffective amount of at least one blowing agent; and activating the atleast one blowing agent to expand the thermoplastic material.
 106. Themethod of claim 105 wherein the thermoplastic material is asubstantially linear ethylene polymers characterized as having (a) amelt flow ratio, I₁₀/I₂ ³ 5.63, (b) a molecular weight distribution,M_(w)/M_(n), as determined by gel permeation chromatography and definedby the equation: (M _(w) /M _(n))≦(I ₁₀ /I ₂)−4.63, (c) a gas extrusionrheology such that the critical shear rate at onset of surface meltfracture for the substantially linear ethylene polymer is at least 50percent greater than the critical shear rate at the onset of surfacemelt fracture for a linear ethylene polymer, wherein the linear ethylenepolymer has a homogeneously branched short chain branching distributionand no long chain branching, and wherein the substantially linearethylene polymer and the linear ethylene polymer are simultaneouslyethylene homopolymers or interpolymers of ethylene and at least oneC₃-C₂₀ a-olefin and have essentially the same I₂ and M_(w)/M_(n) andwherein the respective critical shear rates of the substantially linearethylene polymer and the linear ethylene polymer are measured at thesame melt temperature using a gas extrusion rheometer, (d) a singledifferential scanning calorimetry, DSC, melting peak between −30 and140° C., and (e) a short chain branching distribution index (SCBDI) ofgreater than or equal to 50 percent.
 107. The method of claim 106wherein the substantially linear ethylene polymer has a density in therange about 0.86 g/cc to about 0.90 g/cc.
 108. A carpet tile comprising:a primary backing with a face side and a back side, said primary backingbeing made from a polyolefin; polyolefin yarn tufted into the primarybacking so as to produce a carpet pile on the face side of the primarybacking and loops of yarn on the back side of the primary backing; anadhesive layer of a polyolefin at least partially penetrating theprimary backing, the loops of yarn on the back side of the primarybacking or both.
 109. The carpet tile of claim 108 further comprising asecondary backing fabric which is laminated to the adhesive layer. 110.The carpet tile of claim 109 wherein the secondary backing fabric is anon-woven material made from a polyolefin.
 111. The carpet tile of claim109 wherein the secondary backing fabric is a spun-bond polyolefin. 112.The carpet tile of claim 109 wherein the secondary backing fabriccomprises fibers needle-punched therein.
 113. The carpet tile of claim109 further comprising a second adhesive backing layer.
 114. The carpettile of claim 113 further comprising a layer of reinforcing materialembedded between the adhesive backing layer and the second adhesivebacking layer.
 115. The carpet tile of claim 114 wherein the reinforcingmaterial is a non-woven polyolefin fabric.
 116. The carpet tile of claim114 wherein the reinforcing material is a fiberglass scrim.
 117. Thecarpet tile of claim 113 wherein the adhesive backing layer and thesecond adhesive backing layer both contain an inorganic filler.
 118. Thecarpet tile of claim 117 wherein the second adhesive backing layercontains a higher level of inorganic filler than the adhesive backinglayer.
 119. The carpet tile of claim 118 wherein the second adhesivebacking layer contains between about 30 and about 80 percent by weightinorganic filler and the adhesive backing layer contains between about 0and about 60 percent by weight inorganic filler.
 120. The carpet tile ofclaim 113 wherein the weight of the adhesive layer and the secondadhesive layer combined is between about 20 and about 100 osy.
 121. Thecarpet tile of claim 108 wherein the adhesive backing layer comprises anadditive to increase the adhesiveness of the layer.
 122. A carpet tilecomprising: a primary backing with a face side and a back side; yarntufted into the primary backing so as to produce a carpet pile on theface side of the primary backing and loops of yarn on the back side ofthe primary backing; a first polymeric layer extruded onto the back sideof the primary backing and the loops of yarn on the back side of theprimary backing; a reinforcing fabric adjacent the first polymericadhesive layer; and a second polymeric layer extruded onto thereinforcing fabric.
 123. The carpet tile of claim 122 wherein theprimary backing, the yarn, the first polymeric and second polymericlayer and the reinforcing fabric are all made from a polyolefin. 124.The carpet tile of claim 122 further comprising a secondary backingfabric which is laminated to the second polymeric layer.
 125. The carpettile of claim 124 wherein the secondary backing fabric is a non-wovenmaterial made from a polyolefin.
 126. The carpet tile of claim 125wherein the secondary backing fabric is a spun-bond polyolefin.
 127. Thecarpet tile of claim 124 wherein the secondary backing fabric comprisesfibers needle-punched therein.
 128. The carpet tile of claim 122 whereinthe reinforcing material is a non-woven polyolefin fabric.
 129. Thecarpet tile of claim 122 wherein the reinforcing material is afiberglass scrim.
 130. The carpet tile of claim 122 wherein the firstand second polymeric layer both contain an inorganic filler.
 131. Thecarpet tile of claim 130 wherein the second polymeric layer contains ahigher level of inorganic filler than the first polymeric layer. 132.The carpet tile of claim 131 wherein the second adhesive backing layercontains between about 30 and about 80 percent by weight inorganicfiller and the adhesive backing layer contains between about 0 and about60 percent by weight inorganic filler.
 133. The carpet tile of claim 122wherein the weight of the first and second polymeric combined is betweenabout 20 and about 100 osy.
 134. The carpet tile of claim 122 whereinthe first polymeric layer comprises an additive to increase theadhesiveness of the layer.
 135. A method of making a carpet tilecomprising the steps providing a primary backing with a face side and aback side, said primary backing being made from a polyolefin; tufting apolyolefin yarn into the primary backing so as to produce a carpet pileon the face side of the primary backing and loops of yarn on the backside of the primary backing; extruding an adhesive layer of a polyolefinonto the back side of the primary backing so as to at least partiallypenetrate the primary backing, the loops of yarn on the back side of theprimary backing or both to make a carpet; and cutting the carpet intotiles.
 136. The method of claim 135 further comprising the step oflaminating a secondary backing fabric to the adhesive layer.
 137. Themethod of claim 136 wherein the secondary backing fabric is a non-wovenmaterial made from a polyolefin.
 138. The method of claim 137 whereinthe secondary backing fabric is a spun-bond polyolefin.
 139. The methodof claim 135 wherein the secondary backing fabric comprises fibersneedle-punched therein.
 140. The method of claim 135 further comprisingthe step of extruding a second adhesive backing layer.
 141. The methodof claim 140 further comprising the step of embedding a layer ofreinforcing material between the adhesive backing layer and the secondadhesive backing layer.
 142. The method of claim 141 wherein thereinforcing material is a non-woven polyolefin fabric.
 143. The methodof claim 141 wherein the reinforcing material is a fiberglass scrim.144. The method of claim 140 wherein the adhesive backing layer and thesecond adhesive backing layer both contain an inorganic filler.
 145. Themethod of claim 144 wherein the second adhesive backing layer contains ahigher level of inorganic filler than the adhesive backing layer. 146.The method of claim 145 wherein the second adhesive backing layercontains between about 30 and about 80 percent by weight inorganicfiller and the adhesive backing layer contains between about 0 and about60 percent by weight inorganic filler.
 147. The method of claim 140wherein the weight of the adhesive layer and the second adhesive layercombined is between about 20 and about 100 osy.
 148. The method of claim135 wherein the adhesive backing layer comprises an additive to increasethe adhesiveness of the layer.
 149. A method of making carpet tilecomprising: providing a primary backing with a face side and a backside; tufting yarn into the primary backing so as to produce a carpetpile on the face side of the primary backing and loops of yarn on theback side of the primary backing; extruding a first polymeric layer ontothe back side of the primary backing and the loops of yarn on the backside of the primary backing; placing a reinforcing fabric adjacent thefirst polymeric adhesive layer; and extruding a second polymeric layeronto the reinforcing fabric.
 150. The method of claim 149 wherein theprimary backing, the yarn, the first polymeric and second polymericlayer and the reinforcing fabric are all made from a polyolefin. 151.The method of claim 149 further comprising laminating a secondarybacking fabric to the second polymeric layer.
 152. The method of claim151 wherein the secondary backing fabric is a non-woven material madefrom a polyolefin.
 153. The method of claim 152 wherein the secondarybacking fabric is a spun-bond polyolefin.
 154. The method of claim 151wherein the secondary backing fabric comprises fibers needle-punchedtherein.
 155. The method of claim 149 wherein the reinforcing materialis a non-woven polyolefin fabric.
 156. The method of claim 149 whereinthe reinforcing material is a fiberglass scrim.
 157. The method of claim149 wherein the first and second polymeric layer both contain aninorganic filler.
 158. The method of claim 157 wherein the secondpolymeric layer contains a higher level of inorganic filler than thefirst polymeric layer.
 159. The method of claim 158 wherein the secondadhesive backing layer contains between about 30 and about 80 percent byweight inorganic filler and the adhesive backing layer contains betweenabout 0 and about 60 percent by weight inorganic filler.
 160. The methodof claim 149 wherein the weight of the first and second polymericcombined is between about 20 and about 100 osy.
 161. The method of claim149 wherein the first polymeric layer comprises an additive to increasethe adhesiveness of the layer.